Does PTSD cause dementia?
Post traumatic stress disorder (PTSD) is a common condition in Australian ex-service personnel and veterans. Depending on the type of deployment the rate of chronic PTSD among veteran’s ranges between 10-20%. As veterans age they enter epochs associated with increasing risk of dementia. The Vietnam era veterans are now entering their sixth and seventh decades. As they age more and more will be exposed to the risk of Alzheimer’s disease, vascular dementia, and combined forms, as well as Lewy body dementia and frontotemporal dementias. An important question is whether veterans suffering from PTSD are more likely to develop dementia.
Link between PTSD and dementia
Over last 10 years interest has increased in the possible causal association between PTSD and dementia (primarily Alzheimer’s disease and vascular dementia). A number of potential explanations have been proposed.
1. PTSD is associated with impaired cognition in domains of attention, working memory, verbal memory, new learning, and executive functions. PTSD can be considered as a ‘disorder of memory’. The cognitive changes seen in PTSD reduces cognitive reserve and this can predispose to development of dementia.
2. The cognitive changes seen in PTSD may in fact be very early markers for dementia developing among PTSD sufferers.
3. PTSD and dementia share common risk factors such as traumatic brain injury (TBI), low IQ, limited education, substance abuse, and risk factors for vascular disease.
4. PTSD is regarded as a stress-related condition. Chronic stress can predispose to dementia in the following ways.
(i) Chronic stress is associated with alterations in hypothalamic-pituitary-adrenal axis function and raised pro-inflammatory cytokines. Reduced cortisol levels and allosteric down regulation of glucocorticoid system leads to chronic CNS inflammation and increased cognitive decline.
(ii) Chronic stress is associated with damage to hippocampus and reduced hippocampal volumes. Smaller hippocampal volume is correlated with deficits in short-term memory performance and hipppocampal atrophy is seen in Alzheimer’ disease.
5. PTSD may accelerate the general aging process.
6. Cognitive decline might ‘unmask’ PTSD in older veterans. The combination of dementia and PTSD may cause difficult behaviour problems in these patients.
So far there has been no evidence of a causal link between PTSD and dementia. But this has changed with the publication of two new studies.
The two studies that have raised the possibility of a causal link between PTSD and dementia are –
Yaffe et al. PTSD and risk of dementia among US veterans. Arch Gen Psych 2010; 67: 608-613.
Qureshi et al. Greater prevalence and incidence of dementia in older veterans with PTSD. J Am Geriatr Soc 2010; 58: 1627-1633.
Both investigations are retrospective cohort studies over a seven to 10-year period (1998-2008) using US Department of Veterans Affairs (VA) administrative databases recording clinical contacts in VA clinics and facilities. Diagnoses of PTSD and dementia are based on ICD-9-CM criteria. Dementia diagnoses included Alzheimer’s disease, vascular dementia, senile dementia, frontotemporal dementia, Lewy body dementia, and dementia not otherwise specified. Large numbers of subjects were involved.
This study used VA National Patient Care Database coding clinical information on patients seen from 2000 to 2007. This is an incidence study of new cases of dementia over a seven-year period and the association of dementia with PTSD diagnosis at baseline. Dementia cases at baseline were removed from sample. Potential confounder and shared risk factors between PTSD and dementia were assessed and controlled in data analyses (using adjusted Cox proportional hazard models giving Hazard Ratios [HR]). Potential confounders assessed were age, socioeconomic status, sex, educational and income strata, medical co morbidity (hypertension, diabetes, ischemic heart disease, cerebrovascular disease, neuropsychiatric conditions (clinical depression, substance abuse and head injury), and number of inpatient and outpatient visits to VA clinics.
This study involved 181,000 subjects; 53,000 with PTSD, 128,000 without PTSD. The mean age was 68 years, and 96% were men. The cumulative incidence rate of dementia over seven years was 10.6% among PTSD patients and 6.6% among non-PTSD patients at baseline. This was a strongly statistically significant difference (significant = *). The uncontrolled HR for PTSD versus non-PTSD was 2.31*. That is, those with PTSD had over twice the risk of developing dementia. The HR after controlling for confounders was 1.77*. No difference was found in the HR for the different types of dementia. A comparison of PTSD with other non-PTSD psychiatric disorders revealed a HR of PTSD for dementia of 1.47*.
This study used the Veterans Integrated Service Network 16 Data Warehouse database (10 medical centers in south-central USA) coding clinical information on patients seen from 1998 to 2008. This is a prevalence and incidence study of cases of dementia over a 10-year period and examined the association of dementia with PTSD diagnosis at baseline. Potential confounder and shared risk factors between PTSD and dementia were assessed and controlled in data analyses (using multivariate logistic regression models giving Odds Ratios [OR]).
Two characteristics were used to group subjects; PTSD or no PTSD at baseline, and Purple Heart recipient (PH) or no PH. Soldiers receive a Purple Heart if they are physically injured in active service. To some degree the Purple Heart qualifier might be a proxy for the intensity of combat experienced by the veteran. This study compared four groups; PTSD+/PH-, PTSD+/PH+, PTSD-/PH+, and PTSD-/PH-.
In all 10,481 subjects were included.
Prevalence and incidence of dementia by group
N Prevalence % Incidence %
PTSD+/PH- 3660 11.1 9.5
PTSD+/PH+ 153 5.9 6.8
PTSD-/PH+ 1503 9.2 5.6
PTSD-/PH- 5165 4.5 4.0
Odds ratio after controlling for confounders
Prevalence OR Incidence OR
PTSD+/PH- v PTSD-/PH- 2.3* 2.2*
PTSD+/PH+ v PTSD-/PH- 1.4 1.4
PTSD-/PH+ v PTSD-/PH- 1.2 1.2
PTSD+/PH- v PTSD-/PH+ 2.0* 1.7*
PTSD+/PH+ v PTSD+/PH- 0.6 0.6
PTSD+/PH+ v PTSD-/PH+ 1.2 1.1
The group that included PTSD positive but PH negative veterans had over twice the risk of developing dementia than PTSD negative and PH negative veterans. This group also had nearly twice the risk of developing dementia than the PTSD negative and PH positive veterans. This study also used anti-dementia medication use (cholinesterase inhibitors and memantine) as a proxy for dementia diagnosis – no change in pattern of results was observed.
Both studies have methodological limitations or threats to their validity. First, administrative diagnoses may not be as valid as prospective clinical evaluation. Second, eligibility and access to VA care may bias prevalence and distribution of predictor (PTSD) and outcome (dementia) and confounder variables (Berkson’s bias). It is interesting to note that the PTSD prevalence in the two studies was 2-3%, much lower than usually found in surveys of combat veterans.
These studies represent a first step in establishing a causal link between PTSD and dementia. They provide information about criteria required to substantiate causal links in medicine (the Bradford Hill criteria).
1. Strength of association (effect size etc)
Both studies showed a substantial and significant risk of developing dementia in older veterans who had PTSD at the start of the observation period. The risk was doubled compared to subjects without PTSD.
2. Consistency of association (most studies give similar results)
The findings of both studies were consistent; both in direction of the association and the strength of the association.
3. Temporal relationship (the risk factor comes before the disorder)
Although the studies were retrospective examinations of existing databases, they used data collected prospectively and were able to assess onset of new cases of dementia and the relation to baseline PTSD. Both studies showed that PTSD predicts an increased risk of dementia.
5. Specificity (one factor, one condition)
Both studies used multivariate statistical techniques to control for shared and confounding risk factors. Even after controlling for these variables the risk of PTSD for dementia remained strong suggesting that the presence of PTSD has a unique contribution to risk of dementia. However, the risk of dementia was similar across all the dementia types. One study found that PTSD but not non-PTSD psychiatric conditions had an increased risk of dementia. These results suggest that PTSD is a specific risk factor for dementia as a whole, but not for any particular type of dementia.
Further studies will need to assess whether a biological gradient is present; if the presence of more severe or prolonged PTSD is associated with a higher risk of dementia.
The importance of these findings demand that further studies are undertaken, especially prospective cohort studies. Further scientific enquiry needs to examine the direct links between PTSD and different types of dementia.
It will be interesting to see if these observations can be replicated in Australian veteran populations. How could this be achieved? The Australian Department of Veterans’ Affairs (DVA) has administrative databases on information about accepted service-related disabilities, hospital admission diagnoses, and the use of medications by veterans. These databases could be used to identify cases of PTSD and dementia and examine the relationship between them over time. A very preliminary examination of this data shows trends that seem similar to the findings of the USA studies. More work needs to be done.
Planning dementia services for veterans may need to take into account the higher risk of dementia in veterans suffering from PTSD. There may be a case for dementia to be considered as a service-related compensable condition.
Finally, opportunities for prevention of dementia may be possible. First, avoid or limit the development of PTSD in military personnel. Second, identify and treat PTSD early and effectively in order to reduce the risk of dementia. And third, early detection of cognitive impairment or dementia in veterans suffering from PTSD may provide a chance to prevent deterioration.
Prof Philip Morris.
This is a great article and I’m so glad I came across it! Many people forget about the PTSD diagnosis when these elders also have a type of dementia. Thanks for sharing!
Dear Cindy, thanks for your comments. This potential link between PTSD and dementia is likely to be a problem for traumatic stress sufferers both in the civilian and defence force communities. Philip Morris.
This was an incredibly helpful research review! This clinician thanks you for taking the time to review two articles I would have missed otherwise.
Dear Rachelle, the literature base on this connection between PTSD and dementia is small at the moment, but I hope we get more studies published to substantiate any association. Philip Morris.
Philip, a great article, now we have to get DVA, RMA to amend the SOP’S
Having suffered with PTSD and dementia and now aproaching elder age I see no medication to keep me in the “real world”‘. Since my mental condition was caused from the vietnam war I feel that even this late stage in life, Uncle Sam could help those of us that are going to eventuaolly lose our minds. It’s a sad day for those of us who not only dread the coming days, but will also light the sucidal fuse that took many out of our misery in the early stages when there was no help at all
Thank you for your post. Could I recommend that you contact your local doctor or the VVCS about your health situation. You might find that there are things that can be done to assist you. Philip Morris.
Thank you for this outstanding article and the implications for the treatment of aging war veterans with Dementia. I am currently treating a WW II Combat Veteran with both PTSD and Dementia. Can you recommend any best practices for group therapies which can assist my client with either improving his cognitive skills or increasing socialization and peer support?
Thanks. There is not a lot written on treating veterans suffering from PTSD and dementia with group therapies. You can go to PubMed and search through the literature in the US Library of Medicine on this topic. Also you might like to contact the Australian Centre for Post-traumatic Mental Health and the US National Centre for PTSD for additional information. Philip Morris.
Did you find anything? I’m also looking at treatments for a patient with both PTSD and dementia.
My husband is now in late stage Alzheimer Disease/Dementia. He is 74 and diagnosed with dementia in 2008. He was in the Marine Corps, and while he did not see combat, he witnessed his bunk mate blow his head off. He also was in Paris Island where two other trainees drowned while marching after midnight in the marshlands in quicksand. While in Japan as a Ground control radar operator, he lost a plane while trying to bring it in during a storm which he blamed himself and just recently (2 years) told me about while profusely crying uncontrollably. He gets very agitated and is now considered too violent to stay at home. In the 50’s when he served, there was little talk about PTSD, but I truly believe he has it. He also had chemically induced spinal meningitis. He had injured his knee and was to be operated on but while inserting the anesthesia, which ended up to be contaminated, he instantly got meningitis which put him in a coma for a month. Is there any further evidence showing PTSD relationships to dementia/ meningitis brain damage?
Thank you. I am very sorry to hear of your husband’s predicament. I have not seen links between PTSD and meningitis or brain damage (other than the obvious that military personnel who are exposed to war-trauma may also have a higher likelihood of exposure to concussion impact head trauma and brain damage). I suggest you use Google to navigate to PubMed (US Library of Medicine) and use that search facility to look for literature that examines the PTSD dementia/meningitis/brain damage link. Philip Morris.
What treatment option are there for dementia patients with PTSD
It depends on the clinical situation – specialist psychogeriatrician or geriatrician advise should be sought for the individual case. Sometimes cholinesterase inhibitors can help if the dementia takes the form of Alzheimer’s disease or similar conditions. PTSD symptoms need to be addressed via appropriate medications and psychological/social treatments. Philip Morris.
My husband Tom was diagnosed with PTSD in 2002 and received 40% disability. He received two purple hearts in Vietnam. He lived a good life up until 2004 He suffered from dementia or cognitive loss as recorded by the VA in 2009. He would grind his teeth during the day so loudly at times that I could hear him in the grocery store 2 aisles away. He turned to alcohol. The VA offered programs that did not work for him. 3 times he went to AA treatment centers that did not work. He saw a psychologist weekly outside of the VA. He died April 5, 2013. He could not reconcile his current poor judgement and cognitive loss with the person that he was prior to PTSD. He could not understand his angerYour article is very informative but does not offer any hope. The VA needs to recognize that a veteran is crumbling to pieces and somehow treat him with programs that will address his situation, protect him and provide for him, not just collect data for research. I believe that the VA is trying but the problem is overwhelming and there is no solution.
Thank you for your post. I express my sympathy for the loss of your husband. I note your comments that we all need to do better about this problem. Philip Morris.
Dear Dr Morris, Thank you for providing such excellent and useful information about PTSD and Dementia etc. While I am not a health professional of any kind, but just a regular person with certain mental health issues, I am in a position where I find myself asking certain questions in regards PTSD and the proper diagnosing thereof. I have personally been diagnosed with PTSD due to having been through some distressing events in my life, but wonder if this is a correct assessment or not – is there any validity in this diagnosis for people such as myself, or is it just some kind of trend in psychiatry these days ? I am aware that while two people can experience the exact same event in life, each of those persons may respond/react quite differently to that event, depending on one very critical factor which enters the picture, that of fear, resulting in a profound alteration of one’s view of reality – when fear is present, it can cause one to feel that their very life is at risk in just about any stressful or distressing circumstance – obviously far more pronounced for service personnel in active combat!! How can a soldier NOT feel fear when faced with an enemy who is trying to eradicate you on a daily basis ?! When someone is pointing a gun to your head, or trying to blow you up with one of the many fascinating war toys invented to see how many small pieces a person can be reduced to, there’s not too many ways in which the poor old soldier can interpret that experience. However, in a different setting all together, when the average Joe Blow is diagnosed with PTSD due to traumatic experiences in his life, it can be hard to understand exactly how he could feel that his life is being threatened, as a result. Dr Morris, I wonder if you could provide me with your opinion about the diagnosing of PTSD for those of us who have never served in the armed forces, or been involved in any sort of armed combat etc, or even any other sort of experience where one has been subject to a life threatening situation, like being kidnapped by terrorists, being involved in natural disasters etc etc – hence suffering PTSD as a result. It seems that these days, many people are being diagnosed with PTSD, due to having been subject to, or involved in certain distressing events which were highly traumatic to that person, for whatever reason. In regards this topic, I would like to find out if it is possible for a person (myself included) to suffer from PTSD after having experienced certain stressful or traumatic situations in every day life, as opposed to those experiences that are widely accepted as a definite cause of PTSD i.e. life threatening experiences and trauma, in the course of armed combat etc. Who can make the judgement that a private individual does not, or can not react to certain stressful situations in every day life, in a similar way to that of defence force personnel who find themselves in situations where their life is at risk, and hence suffer from PTSD ? I hope that my ramble has made some sense to you Dr Morris, and been somewhat intelligible. I look forward to reading a reply from you, and finding out what your expert opinion is. Thanks again for the opportunity to engage with you here…. all the best to you ! Leonie
Thank you. I do not make comment publicly on individual cases. I suggest you ask your GP to refer you to a specialist psychiatrist for an opinion. Philip Morris.
I ran across your article while looking for a new medication alternative for my great Uncle. He is a WW II veteran who has seen three theaters of war. He is a congressional gold medal recipient. I have been fighting with the Bay Pines VA non stop that he suffers from PTSD , They say they can’t tell at this point because he shows more severe signs of dementia at the age of 91. He is now severely sedated on valproic acid which is not acceptable… We now even have Congressman Bill Young helping out with his case for more compensation for his care. He becomes very combative and agitated .Everytime he is in the VA hospital they keep him in big leather shackles… But yet they still aren’t convinced its PTSD, really….when they came back from war they where told to shut up , don’t talk about what had happened , just go on with life. As I see it now the Dementia has removed the suppressive filter on his brain and actions… Do you have any medication recommendations???
I served in VietNam from Oct. 65 till June 65. The U.S. Army has me listed with PYSD liability. They have also said that I am in early stages of Alzeimers/Dementia. I just happened to look for a connecdtion on the internet and found this article. I also found an article by Dr. Mark Kunik a psychiatrisr at the Michael E. DeBakey VA Medical Center in Houston, Tx. where I was diagnosed and given treatment for PTSD. I am also being given medication for the Alzeimers/Dementia. They have not said so to me but I believe the implication is strong enough.
The Australian government through its Repatriation Medical Authority (RMA) has recently approved PTSD as a causative factor for Alzheimer’s disease in the veteran population. This ruling is published as a Statement of Principle (SOP) on the RMA website.
May I simply just say what a comfort to uncover someone who
actually understands what they are talking about on the web.
You definitely realize how to bring a problem to light and make it important.
More and more people need to look at this and understand this side of the story.
Thank you for perhaps the most level headed thing I have read today. I also can be helpful here 🙂 I mostly use
http://goo.gl/yZolHvto edit my PDFs. I think it also allows you to to create fillable pdfs and esign them.
Thanks. Occasionally I have come across similar histories.
This was truly informative. I have a disabled vet that has severe PTSD, no retired due to this. I believe that he has had a TBI while in Iraq /Afghanistan and yet the VA won’t test him for it. I believe due to combat related injuries and stress, that he has onset dementia. Reading this brings some clarity to believe I know thus true. Hopefully more has come out since this article was released. Keep us informed if any further information.
I am researching documentation on PTSD as a cause of Dementia. especially in individuals who received the Purple Heart in Vietnam. I am hoping to connect the PTSD with my husband’s early onset Dementia. Any information is appreciated.
if there is any correlation between PTSD, what must the correlation be with C-PTSD … Complex-PTSD … for sufferers of traumatic events for longer periods of time ? … have there been studies on this?
This is 12 months since last post. However as my husband died in 2014 from brain damage from LBD plus PTSD ( undiagnosed / untreated) I am finally reassured that medical profession and Services are starting to recognise & assist those who need help most.
I am aware of work being done by my husbands employer, Victoria Police Force, & I believe they are making inroads with their peer support volunteers. The best support of all, to have confidential contact with one who is on the same journey.
My other concern is who is caring for the carers.
I had a background of nursing but nothing prepared me for our own journey.
Our GP had little knowledge at all. Thankfully I found out about the Austin Hospital Dementia Research Unit here in Melbourne. It was there we got a definitive diagnosis and some guidance as to how the disease may progress.
Then our struggle began.
Eventually my husband agreed to go to a Dementia Day Centre at a Nursing Home near where we lived. It helped us both tremendously.
However the hallucinations became so violent linked with past episodes in my husbands life it was terrifying for us both.
It was with relief and great sadness when my husband died in 2014 aged 76
Thank you for sharing your story with me. I can appreciate but not really know the anguish you both went through. I hope you can be of service to others with similar journey to face. Is there any volunteer role for you in your area? Dr Morris.