 Now, today's webinar is, They Are Older Now, a snapshot of self-identified veterans in the Canadian logistical study on aging. Welcome to our distinguished speaker, Dr. Christina Wolfen. Dr. Wolfen is a professor in the department of epidemiology, biostatistics, and occupational health in medicine at McGill University. She is a senior scientist in the brain repair and integrative neuroscience or brain program at the research institute of McGill University Health Center. Her research focuses on the study of neurological disorders in the population, such as most multiple sclerosis, Parkinson's disease, epilepsy, ameliotrophic, lateral sclerosis, and dementia, with an interest in identifying the burden, frequency, and risk factors. She is also our CLSA co-principal investigator and leads the neurological conditions initiatives and Veterans Health Initiative. Finally, she is the director of the CLSA Statistical Analysis Center. Again, once more, a reminder that there will be a question and answer session at the very end of the webinar, but feel free to write in the questions. Any questions or concerns at any time during the webinar in the chat box and we'll address them then. So, now we'll turn it over and welcome Dr. Christina Wolfen. Thank you, Carol. Thanks for the introduction. I'm very pleased to be here today to make this presentation. And it's timely, November 13th, just two days away from November 11th. So, I took this opportunity to accept the invitation to present now. What I'm going to talk about is, I think, what is a unique initiative within the Canadian Longitudinal Study of Aging, and that is a self-identified Veterans within the cohort. So, one of the first questions you might ask is, why would we be interested in studying Veterans? And there are a number of reasons for that. I mean, I think, if you think about aging studies over the last couple of decades, many, certainly in Canada and in the UK and in the United States, many of those individuals who were parts of longitudinal studies of aging were subject to wartime exposures perhaps either at home or overseas, and that could have shaped their aging. And that's why one of the reasons why one might be interested. And certainly, of course, these individuals served on behalf of the population. And it's been estimated that in Canada, there are 700,000 Canadian Armed Forces Veterans. So, that's a fairly significant proportion of the population, and these individuals are aging. Some, of course, who were overseas have returned with injuries that may now, even years later, affect their health. And there is some literature to support late life effects of earlier injuries. So, military service could be an important determinant of health and possibly of healthy aging. One of the aspects of this research that struck me is that it is actually very difficult to identify Veterans once they release from the military. And in fact, my first foray into the area of research in Veterans was spurred by work that I did on a couple of Institute of Medicine panels in the United States where I was asked to participate in panels to look at the health effects on the military of exposure to insecticides, pesticides, and solvents, and then also in a subsequent committee to look at the possible risk of amyotrophic lateral sclerosis in returning Gulf War Veterans. Sitting around the table as the only Canadian on the panel, more than once I was asked, well, what kinds of studies do you have in Canada of Veterans? And in those days, and that was early 2000, 2003, 2006, there was really very little that I could tell them. And that sort of struck me as a gap. As Carol explained, my area of interest is in neurological diseases. So, I put aside the issue of Veterans until the CLSA came to pass when I saw that there was a unique opportunity. So just to put some of the numbers in context, in terms of service from Canada, Canadian Veterans, in World War I, there were approximately over 600,000 troops sent and one third of them were killed or wounded at World War II. And this is the part of the cohort that some of whom are included in the CLSA. More than a million troops were sent and over 100,000 were killed. Canada also participated in Korea and you'll see the numbers there. Canada did not send troops directly to Vietnam, but there were over 30,000 Canadians who volunteered and served in Vietnam. The Gulf War, Afghanistan, and of course now a lot of the troops, the Canadian Armed Forces, are involved in peacekeeping. So this is a significant portion of the population in the past and currently who are put in situations which may in the short term, of course we know, but in the longer term as they age, have some impact on their health. So what do we know about the health of Veterans in Canada? Well, I said that we knew very little and in 2013 I was working with Dr. Catherine Tansy and we put together a scoping review of the level of information of health of Veterans in Canada and there was in fact very little information. Since that time, fortunately, they've been in a couple of large-scale studies generated through Veterans Affairs Canada and Statistics Canada looking at the transition to civilian life. But these Veterans were those who were released between 1998 and 2007. So they are in fact younger Veterans than one might be interested in relation to World War II and even the Korean War. There's also some extremely interesting work that is just coming out now where Alison Mahar and Alice Aitken have identified Veterans within the administrative databases in Ontario. In fact, there is an identifier within the Health Administrative Databases in Ontario, so they have been able to start a research program looking at these individuals who were released between about 1990 and 2014. I haven't actually been able to find any large-scale research that looks at the health psychological health or physical health or health service utilization of individuals released prior to 1990. So the Canadian Launch Tunnel Study on Aging Veterans Health Initiative was something that evolved in the planning stages of the CLSA in around about 2005, 2006, 2007, where the CLSA PIs connected with the Research Directorate of Veterans Affairs to discuss possible research opportunities within the CLSA. What was really I think quite a remarkable initiative is this culminated in a partnership and Veterans Affairs Canada agreed to provide some financial support to include two supplementary modules in the baseline assessment of the CLSA to be asked of all participants in the CLSA. And that was a set of Veteran Identifier Questions and also a screening tool for post-traumatic stress disorder. I'll talk about those a little bit more later. So I know this is the CLSA webinar but I don't know if everyone on this webinar is fully familiar with the CLSA, so I do have a few slides to take you through that. So the CLSA is a strategic initiative of the CIHR. Planning began in 2001 and it took I would say close to 10 years to actually get it funded and implemented. There are three co-PIs, Carmen Durant McMaster who's the lead PI, Susan Kirkland at downtown myself. That's not to mention that there are more than 160 co-investigators from across Canada involved. It's multidisciplinary including biology, genetics, medicine, psychology, sociology, etc. It's basically trying to look at all aspects of aging and it's the largest study of its kind in Canada following currently following 51,000 participants who were aged 45 to 85 at enrollments and the goal is to follow them from baseline for at least 20 years and I'll say at least because we would hope to get funding beyond that. Well I think people after me would hope to get funding beyond that. So CLSA has both an aim and a vision and the aim is as a longitudinal study of aging to examine transitions and to capture trajectories to enable the identification of modifiable factors with the potential to inform interventions and strategies to improve the health of populations as they age. That is the fundamental aim of the study and that is how the study was designed in relation to the selection of measures that are included. CLSA also has a vision and its vision is to create a research platform and infrastructure so that what that means is that researchers across Canada and actually outside of Canada international researchers have the opportunity to obtain the data from the CLSA and eventually to obtain the biospecimens from the CLSA and to use the infrastructure for their own purposes. So just in encapsulating the design overview I put some actual numbers in here now 51,338 women and men in Canada who were aged 45 to 85 at baseline were recruited. They're recruited in two levels of data collection on the left-hand side of the slide you'll see 21,000 individuals participate by through questionnaire interviews over the questionnaire interviews over the telephone only we call that the tracking cohort. These individuals are randomly selected from all 10 provinces and are truly representative of the Canadian population insofar as that is possible with a volunteer cohort. On the right-hand side we have over 30,000 people who have more in-depth assessment than the telephone group than the tracking cohort. So these individuals undergo an in-person interview in their home and it's essentially the same interview that is done by telephone. So at the end of the day we have over 50,000 individuals who have completed the same questionnaire. They then come into one of 11 data collection sites that have been built across Canada for physical assessments and biospecimen collection. Now due to the nature of the comprehensive cohort that the individuals who come for the full physical assessment the sites are essentially around academic areas. They are not randomly distributed across the country. There are 11 sites in seven provinces and individuals for that component of the study were recruited with an geographic radius of 25 to 50 kilometers for recruitment. So as I said this is a 20-year study with follow-up every three years and we are actually currently coming towards the end of our first follow-up. So we completed the baseline assessments in 2015 turned around very quickly to begin our first follow-up on all 51,338 participants. We're also working very hard to establish data linkage with healthcare mortality and disease registries. So how do we recruit these individuals? We use three different sampling frames. We started off with a partnership with Statistics Canada through the Canadian Community Health Survey on Healthy Aging. We had Statistics Canada include a sharing question within the questionnaire and so individuals who agreed to share their contact information with the CLSA were then forwarded to the CLSA for our own recruitment. This is the first Statistics Canada had never released names to researchers in this way before. That yielded about 8,000 participants so that wasn't enough for our 50,000 planned cohort. We then entered into partnerships with provincial ministries of health using the health card registration databases. What was done there is mail-outs from the ministries of health were sent to the individuals with the framework within the types of people that we wanted, the age range, sex distribution, etc. Those individuals then returned a consent to contact form and were followed up by the CLSA. That was not a successful strategy in all provinces and so in the remaining provinces we then did random digit dialing. We're very fortunate however to have very strong methodology working group, experts and international experts in sampling and they have created sampling weights to enable us to use the full sample so not to worry about the fact that we have three sampling frames. So one important point here is to discuss the exclusion criteria at baseline or at recruitment. We had to follow the exclusion criteria put in place by the Canadian Community Health Survey in order so the rest of the sampling things had to follow that. So the first five are the exclusion criteria that come from PCHS. So we excluded residents of the three territories, those living in an institution, those living on a First Nation reserve and I've highlighted. We excluded full-time members of the armed forces and we excluded temporary visa holders. The CLSA added two more criteria in relation to the way we were going to conduct the study. Individuals who were cognitively impaired at baseline were excluded. Certainly if individuals become cognitively impaired within the study as we as we follow them up they are included because of course that's an important part unfortunate important part of aging and also we were only able to conduct the study in English and in French so if an individual is unable to communicate in French or in English they have to be excluded. So this is a very busy slide just to show you some of the modules for the baseline questionnaire that were asked of all 51,000 participants just loosely categorized them into demographic health and social. I highlighted here in the demographic we have the veteran status and in the health we have a PTSD screen. The additional assessments that were done sorry about the formatting of this slide the additional assessments that were done for those individuals who came in were some basic and symmetric measures some measures of function and then the physical measures including a blood sample and a urine sample. What I'm going to talk about today in relation to the veterans really only deals with the self-report information. We haven't yet completed the analyses using the physical measures. So how did we identify veterans in the CLSA? As I said we used to set a veteran identifier questions that were provided to us by Veterans Affairs Canada and there was a recent publication in 2006 by Linda Van Til et al that described these questions and actually recommends or I think encourages researchers to include such questions in large-scale surveys because as I said we do have a bit of a challenge identifying veterans in Canada. In the 1951 census there was a question on veterans and then again it was used in the 1961 census the 1971 census and the 1991 general social survey and in 2003 a Canadian community health survey used the questions but we really do not have a way of registering these individuals to know who they are how to find them and how to link their information with health registration databases except the work of Alison Mahar and LSA Kenan Ontario. So as I said we used a PTSD screener. This was asked of all CLSA participants not just veterans and it was used over the phone and in the face-to-face in-home interviews. It is a screening tool and these are the questions that are asked. It's very short it doesn't take very long to implement and we did determine that it had been used over the phone in other surveys. So it was validated in the US Veterans Affairs primary care setting and it's been shown to have good sensitivity and specificity compared to a clinician administered scale. It is a screening tool it is definitely not a diagnosis. It does reflect DSM-4 diagnostic criteria using a score of at least three out of four as the screening threshold. So individuals who score three or four on this tool would be determined to be PTSD screen positive. There's been some recent work to modify the tool itself to reflect DSM-5 and so that there's a revision called the PC PTSD-5. Obviously we're not using that in the CLSA because it's more recent than our implementation. So I'm going to get right to giving you some baseline data and I'm going to focus on the self-reported veterans although of course in some results I will be making comparison with the full cohort. So here we go. So here are the numbers. So I've separated out the tracking cohort from the comprehensive cohort. So you'll see we have we identified using these questions a total of 3558 Canadian veterans, 909 non-Canadian veterans for 4467 veterans in total. We did identify 68 individuals who reported current military service. They slipped through the eligibility criteria and in fact what was quite remarkable is this question was really well answered with only 12 out of 50,000 people having missing data. So some very simple descriptors looking at the age. I suspect none of you would be very surprised to see that the age of the veterans is older than the full CLSA cohort by a few years and the non-Canadian veterans are the oldest group. Interestingly enough the age range is the same. Not surprising I'm sure to anyone they're predominantly male. About 50% of the full CLSA cohort is male female. That was by sampling design. I've highlighted the number of females that we actually have amongst the veterans which I think is important because this is a very in days past there were very few female veterans so I think it's nice that we have a reasonably large size there and then I've also reported the marital status of these individuals. This is a rather busy slide. I wanted to show you where these veterans came from. In the first column you see we have the full sample so that is the individuals that were collected in the baseline all 51,000 and the distribution of individuals is in relation to our sampling scheme. The Canadian veterans are very quite similar in the sense of the distribution of where they live. Slightly more Canadian veterans living in Nova Scotia than in the full sample but otherwise maybe slightly fewer living in Quebec than in the full sample but otherwise quite similar. There is a big difference with the non-Canadian veterans which is not surprising because the non-Canadian veterans are immigrants to Canada and I suspect that this reflects at the time that they came where the most popular provinces were to immigrate to. So British Columbia was one and Ontario slightly higher. New Brunswick was quite low and Nova Scotia was low. New Zealand PEI pretty low. So I think that that just reflects the immigration patterns. I did want to take a look about the non-Canadian veterans because as far as I have been able to tell there's actually very little information in Canada on veterans who served in other countries or veterans of other armed forces. So I just have this chart here to show you the most commonly reported country of service. I don't think it surprises very many people that about a third of the non-Canadian veterans were veterans of the UK forces. 12, 13 percent from the US, 5 percent from the Netherlands, 7 to 10 percent from France and then a small percentage from Germany. They were actually looking at the raw data because we have this in open text. There were 253 countries reported in the data but I'm only reporting those with more than two or three percent. The type of service, the question, the veteran affairs, veteran identifier question asks the type of service. So we have Army, Navy, Air Force and Reserves. I didn't include the other category here because we had no understanding of what the other category can be but what you see is a difference in the percentage of service in the Army depending on whether there were Canadian veterans or non-Canadian veterans. The red refers to the non-Canadian veterans and the blue to the Canadian veterans and the green is to the total number of veterans. So most people served in the Army or in the Reserves. So what was their age at CLSA enrollment? So we're talking about between 2012 and 2015. The red bar refers to the non-Canadian veterans and the blue bar to the Canadian veterans. Again, totally consistent. The non-Canadian veterans are older. 25 percent of them are between 75 and 79 in enrollment and 20 percent of them are over the age of 80. This reflects the fact that they had to serve in another country and then came to Canada afterwards. The duration of military service, we had services a little of six months all the way up to 30 years of service within this cohort. The vast majority had service less than five years. And again, the non-Canadian veterans, nearly three quarters of them had had service reported service of less than five years. Again, this is completely consistent with individual serving and then coming to another country. So what were the join years? I think this was important because we wanted to try and get established where, you know, what conflicts these individuals may have served in. We didn't don't have that information in the question. So basically, we just had to categorize it by year. The majority of individuals in both Canadian and non-Canadian veteran groups served between 1950 and 1959. Very few recent join years. I just want to give you, these are really preliminary results. One of the things that we were able to do with these data was to actually estimate the number of veterans in Canada between the ages of 45 and 85. And the estimate that we came up with, and again, these are very preliminary results, which we have to verify approximately 700 and say 20,000 Canadian veterans between the ages of 45, 45 and 85, and 185,000 non-Canadian veterans between the ages of 45 and 85. So this is over 900,000 veterans in that particular age range that we could estimate living in Canada. I believe that these are underestimates for the total number of veterans because of our exclusion criteria. We excluded people living in institutions. We excluded the territories. We excluded people who had current cognitive impairments. We also, of course, have the age range. So we're only talking about people age 45 to 85. This doesn't include veterans younger than the age of 45 or those older than 85. And there are the average age of World War II veterans is about 93, I believe. So we would have excluded those. And also, the timing of the CLSA baseline, we're talking about 2012 to 2015. So now I want to give you a little bit of some preliminary results on health status. I put on this slide both self-reported health, which is the first set of three columns, self-reported mental health, which is the middle set of three columns, and self-reported healthy aging. You'll see that there seems to be very little difference between the non-veterans in blue, the Canadian veterans in red, and the non-Canadian veterans in green. I think if you wanted to talk about trends, one could argue that the veterans seem to be reporting slightly less, very good to excellent healthy aging. But if you look at the numbers and the percentages, they really are quite similar. So I pulled out a few conditions that we looked at within this cohort. And I didn't bring out the conditions that had a lower than a 5% prevalence. And these are age and sex adjusted. So PTSD and non-veterans, we found prevalence of 5.2%, which increased in the Canadian veterans and then was highest in the non-Canadian veterans. I think with the mental health disorders that we have, and this, of course, the anxiety mood disorder and depression are really self-reports, the depression is based on the CESD. What we do see is we do see slightly higher prevalence in the Canadian veterans and the highest prevalence in the non-Canadian veterans. And these are age and sex adjusted. My original analyses, I thought that age was responsible for this, but now that we've adjusted for age, we still see an effect. If we look at some of the physical chronic conditions, that the high blood pressure, heart disease, cancer, osteoarthritis of the knee, hip, and hand, we either see very little difference or, in fact, slightly better outlook for the veterans. And again, there are lots more analyses to do on these data. So this is just your snapshot, as I said. I was, of course, very interested since we included the PTSD screening tool to look at that within the veterans. And in fact, here we look at the score. Remember, the score can be zero, one, two, three, or four. There are just five items. The vast majority of individuals in the full cohort, the non-veterans, Canadian veterans from the non-Canadian veterans did not score anything on the PTSD tool. So 75 to 76 percent scored zero. It's difficult to say that we see any real pattern here. Again, slightly higher, I think, in the non-Canadian veterans. But clearly more analyses to be done here. So one of the things that we wanted to do is to take a sort of a broad look at factors associated with PTSD screen positive versus screen negative. And again, these are cross-sectional data. So it's very difficult to make any interpretations of what comes first. I've highlighted blue and then black just to separate out the various different variables. I just wanted to show you this is the full sample. So this includes the non-veterans. What was interesting, we found that there seemed to be an increased odds ratio in relation to retirement. So PTSD screen positive more likely in those with complete retirement or partial retirement relative to not being retired. There appeared to be an association between being female and PTSD screen positive. Both the Canadian veterans and the non, well, the Canadian veterans for sure had a statistically significant odds ratio in relation to PTSD relative to the non-veterans. The Canadian veterans didn't reach statistical significance. The non-Canadian veterans didn't reach statistical significance, but that could probably be a numbers thing. Being married relative to being single appeared to be, I don't want to say protective because there's no directionality here but was associated with less likely screening positive education. We see the association such that higher levels of education seem to be associated with less likely screening positive PTSD. And there appeared to be a slight protective effect in being in the comprehensive group rather than the tracking group. So that's just looking at the full sample. So here everyone is included the non-veterans, the Canadian veterans, and the non-Canadian veterans. Then I wanted to look just at the veterans as a group themselves, looking, pooling together the Canadian veterans and the non-Canadian veterans. And this is the best fitting model. What we found was a slight association with age whereas individuals, older individuals were less likely to screen positive for PTSD. But again, we saw the retirement effect with a slightly higher odds ratio this time. So individuals who were completely retired were more likely to also screen positive on PTSD. Those who are partly retired, slightly more positive, more likely to screen positive PTSD relative to people who are not retired. So the retirement variable is coming back. Now just looking at the group of Canadian veterans, because we know that the non-Canadian veterans bring some other factors with them in relation to their heterogeneity. So what we saw just looking at the smaller group now, Canadian veterans, about 3,500 individuals, we saw the inverse association with age, the retirement variable was retained, and here there was an army indicator. So individuals who reported service in the army relative to any other grouping in the Navy, Air Force, or reserves were more likely to screen positive on the PTSD screening tool. The tool, we have no diagnosis of PTSD. So one of the things we did is to just look and see how scores on this tool and also screen positive versus screen negative on this tool were associated with other mental health measures and again cross-sectional data. We saw that we got the anticipated or at least hypothesized relationships between the screen positive and self-reportive mood, anxiety, disorder, and depression. So those individuals who screen positive were all also more likely to report having mean tool. They had a mood disorder, anxiety disorder, or depression. We found the inverse association with satisfaction with life. So these individuals were less likely to report high levels of satisfaction with life, high self-rated health, high self-rated mental health, or high self-rated healthy agent. So these are sort of the anticipated relationships that we saw which were somewhat comforting, which shows that this measure seems to be at least acting in the same way as other mental health measures. So sort of what are our preliminary findings? And these are very preliminary. There's a lot more work to do. So self-reported veterans appear to be very similar to non-veterans in relation to self-reported physical conditions, at least with those with a prevalence of at least five percent. We didn't see any major differences amongst the veterans and the non-veterans. What we did see, I think, suggests a slightly higher self-reportive measures of some mental health concerns in relation to PTSD, mood disorder, anxiety disorder, and depression. And just to emphasize again that these were age and sex adjusted when we presented them. And these seem to be most apparent amongst non-Canadian veterans. What was interesting was the robust finding of retirement as a correlate of positive PTSD screen. And interestingly enough, this is consistent with some other studies that have shown what has been suggested as a sort of a resurgence of PTSD symptoms following retirement or around the time of stress thinking about retirement. But as I mentioned before, these are cross-sectional data. So we don't know whether the factors that are associated with screening positive on a PTSD screening tool may actually contribute to someone retiring. So we really don't know what direction is going on here. But these data are, as I said, consistent with some other studies. There is a recent study that was reported on Vietnam veterans that, in fact, 40 years following their service, there was new evidence of PTSD that was directly linked to that war service. How we investigate this in the CLSA, I think we'll have to do further analyses to see whether this is a real finding or whether retirement is just a proxy for something else. So what are the limitations? There are a number of limitations. What we have, and I think the first thing is that we have self-reported veteran status. We don't have any way to verify that these individuals are truly veterans. I think, and the paper that I mentioned that Linda Van Til wrote in 2016, I think she suggests that there's probably no reason for people to self-report they are veterans when they're not. I think perhaps people may under-report veteran status depending on the experience they had in the military. So I suspect that there are probably more there. I certainly have anecdotal reports of individuals who served, who did compulsory military service in countries like Israel and South Africa actually would not regard themselves as veterans. So I think we probably do have some under-reporting there. Obviously right now we're just using the self-reported health measures. As I said before, the PTSD screen is not a diagnosis of PTSD. It is just a screening tool. It's been used widely and has been validated, but again, it's a screening tool. The data are cross-sectional, so we cannot really talk about cause. We can't really talk about predictors or protective factors. So what are we going to do? Well, I think we have to do much more detailed analyses to confirm the performance of the PTSD screening tool. We can look at much more detail in some other analyses in relation to some of our tools of psychological distress that we included in the CLSA. As I mentioned early on in the talk, we did not include the objective measures of health and we did not include the cognitive measures. So I think that that's probably one of the priorities. We should look at the comprehensive participants, so the individuals who came for the full assessments, and look to see whether we can confirm some of these findings in relation to the physical characteristics looking at the more objective measures. So I'm going to just want to do some acknowledgments here. Obviously the first acknowledgement is to the CLSA participants, and I should say that the data analyses that have been done here were supported by the contract from Veterans Affairs Canada and also from a CIHR catalyst grant, and here I just include the general acknowledgement for the CLSA. So overall, one of the things I want to say is I think that the data that we have on the self-reported Veterans, even with the caveats I gave, are unique resource within Canada to have a group of individuals who did not know they were going to be asked questions about whether or not they were Veterans. They answered, and in fact the answers of the Veterans have the lowest level of missing data of any of the the rest of the participants in the CLSA. So I think we have the opportunity with this sample to do some interesting work once we dig a little bit deeper. I also haven't investigated any differences between males and females in the physical health and the mental health, and I think that that's important to do. So with that, I think I'm going to stop here and certainly got plenty of time for questions. Thank you very much Dr. Wolfen. That was an excellent presentation, very interesting. I'd like to thank you for your continued leadership in the CLSA as well. We'll open it up now to questions. As a reminder, muting will remain on, but you can enter your questions into the chat box in the bottom right hand corner of the WebEx window. I don't think there's been any questions so far, so we'll go ahead and give people a little time to ask questions through the chat box, and I'll go ahead and field what for myself. So did you look at any comparisons with other countries, particularly the U.S. or European veterans, particularly with the U.S. because of the different health care programs and the different Veterans Affairs Medical care programs that might be an interesting comparison? Yeah, well that's one of the things that's going to come next, because it actually took us quite a lot of time to identify exactly, to sort of clean up exactly who were the veterans and distinguish the Canadian veterans from the non-Canadian veterans. There are a number of studies, as you can imagine, there's actually a lot of studies in the U.S., but they tend to be focused around quite reasonably specific types of veterans, so there are studies on Vietnam veterans, studies on Gulf War veterans, studies on Korean veterans, and so it's a little bit difficult to do the comparisons, as I said, that we don't really know whether the individuals were veterans of the Korean War or whether they were Canadians serving in the U.S. military in Vietnam, so some of the analyses are a little bit difficult to do. The comparisons that we made are sort of based on some of the results that we've seen, you know, we've seen in other studies looking, for instance, at obviously the mental health outcomes, and there are some things we can't look at, infections, for instance, cirrhosis we couldn't look at, but we have tried to look at some things. I want to dig deeper, look at the musculoskeletal. We didn't have enough numbers to really look at some of the neurological conditions, we couldn't really look at Parkinson's disease, and obviously dementia would have been excluded at baseline in the CLSA, so they're informed. We informed our analyses with previous data, but I think we have a sort of a unique situation here in Canada. I see a question here. Yeah, I'll go ahead and read it. Okay. Yeah, so this is a question from Allen. Yeah, so was there a difference in cancer between veterans? Oh, it looks like there was. No, we haven't had a chance to look at the subtypes yet. We do have a little bit of information in open text on the cancer subtypes, so we could look at that. So thanks. That's something we will look at. Can you mention there's a wealth of things we could, different directions we could go in? So thanks. Yeah, that's something we would look at. Or someone else could look at it because these data are available to the research community. Did you show any difference between the cancer between veterans and non-veterans? Was there a slight? There was a slight percentage difference, but we only really adjusted by age and sex, so we haven't looked at any other characteristics. So talking about kind of that future directions and work, are you going to be looking at kind of a cohort effect maybe from the different conflection questions? Yeah, well, I think follow-up to cancer, thinking of more modern issues versus cognitive decline for older veterans, that type of thing. Well, one of the things, and that raises a very important point, one of the things we haven't yet done, we've looked at them as a group, looking at the Canadian veterans and the non-Canadian veterans. One of my plans is to arrange them on timelines according to their joint year and release year and to try and establish where it's likely they might have served or what conflict they would have been in the military during. That we haven't done, we've looked at duration of service and joint year and release year, but we haven't mapped that on to the Canadian military history of when the troops were sent to various places. So we will look at that, but we don't have any Gulf War veterans in this group. Right, yeah. Well, we'll wait for a couple of other questions to come in. I was struck by how much PTSD there seemed to be for non-veterans. Was there an actual, there was a significant difference between being a veteran, a Canadian veteran and having a higher relationship with PTSD, but there's a lot of PTSD out there for the general population as well, it seems like, for older adults. Yeah, well there's a growing area of research. I hear myself echoing here. Yes, so there is, there's a growing area of a research on something called late onset stress symptomatology in older adults that can manifest itself in PTSD-like symptoms and some studies have actually shown in older adults to be as high as 12%. PTSD, of course, is a reaction to a stress and that stress can be death of a spouse, it can be a traumatic event, any kind of a traumatic event. We don't know what the traumatic event is in the individuals in the CLSA, but even retirement. So it makes sense when you think about it that older people having lived longer and having more happen in their lives could be at higher risk for PTSD-like symptoms. So yeah, so that's another thing I want to look at and that's why I'm really pleased that we asked the PTSD screener of all CLSA participants, not just those whose head that they were veterans. This allows us to make an internal comparison and you're right. I mean it is a fairly high percentage of individuals who screen positive who are not veterans. How that relates to their aging is another question and I've already seen in some analyses that other researchers are doing on the CLSA data that they have actually included this variable as a measure of mental health, which is why I think it's important that I, one of the things I really want to do is to take the PTSD screen and investigate it in relation to the other measures. You know, maybe it's a proxy for other measures, maybe the other measures are proxies for it. So I need to look at it again, but you're right. There is a higher than expected prevalence of PTSD screen positive in the non-veterans as well. So do we have any other questions from the field? We can spend a couple more minutes on question and answers. Well, I'll do one final one for myself. There's no open text information on retirement. There's no, you can't look at the reasons for the retirement or the age of retirement as kind of that. Oh, we can. We can. We can. We can. Oh, I see there's a question. Yeah. From Jim Thompson, your PTSD prevalence numbers are very interesting. Prior to Canadian general population estimates have been much lower, less than 2%, but about as expected, they should be higher. Your prevalence is based on the PCP, PTSD, symptom measures are interesting. So I think that feeds back into the conversation we were just having, but it is a very interesting finding. Yep. I mean, it seems like a small percentage, but when you round that out to, you know, how many individuals we're talking about in this age range, I think that's quite interesting. So thank you. But I just want to say one last thing. If anybody has any specific questions for me about this presentation or this whole area of research or interested in using the CLSA data in relation to the veterans, I'm very happy to communicate with anyone. It's, I think it's a unique small database, but I think it's unique. And as I've said in the very beginning, this is a research platform. So I would be really interested if we could, you know, get a kind of a consortium of people interested in veterans' health to work around these data. It'd be great. We did have another question roll in. So the health indicator preferences are very similar to the findings from CCHS 2003, which included a veterans' identifier and very different from the LASS survey in 2010. Yeah. 2013 and 2015, which looked at former CCHS members aged 20 to 65 roughly. Do you want to speak to that? Well, our folks are older. That's the only thing I can say about that. So, you know, and I think that's the transition to civilian life, the LASS surveys have individuals releasing, I think, I mean, obviously the questioner knows better than I do, but I think 1990 to 2014 or 1998, 2013. So these are mostly younger veterans. Well, they're not veterans that released a long, long time ago. Most of our people released far, well before that. Yeah. And looking at the different associations between all the things they're looking at with different surveys will be interesting in the future as well. Would you do the further analysis? Absolutely. Absolutely. I mean, I think this is really an emerging area of research in Canada. And I think it's a very important area of research. And we already have some leaders with Alice Akin and Linda Van Till and Alison Mahar doing some very interesting stuff. Well, thank you again. It was a really very, very nice presentation. So we appreciate it, particularly for this month of remembrance. Thank you. So I'd like to remind everyone that the CLSA Data Access Request applications are ongoing. If you're interested in gaining access to CLSA data, the next deadline for applications is on January 29, 2018. You can visit the CLSA website under Data Access to Review Available Data for their information and details about the application process. I'd also like to mention that our next webinar is scheduled for December 12th. We'll be talking about visual impairment, eye care and visualization, with Dr. Ellen Friedman. Please register and join our next webinar.