History of Cannabis Smoking Linked to Memory Complaints in Older Women

Among 15,378 women over 65, those who had ever smoked cannabis were 27-30% more likely to report cognitive complaints, with regular past smokers at 61% higher risk than never-users.

Ding, Guoyong et al.·Neuroepidemiology·2026·Moderate Evidencelongitudinal
RTHC-08227LongitudinalModerate Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
longitudinal
Evidence
Moderate Evidence
Sample
N=15,378

What This Study Found

Ever smoking cannabis was associated with increased odds of subjective cognitive complaints across three follow-ups: OR 1.27 (2nd), 1.28 (3rd), 1.30 (4th). Regular smokers had stronger associations than occasional smokers (OR 1.61 vs. 1.19 at 2nd follow-up). Results were consistent across subgroup and sensitivity analyses.

Key Numbers

15,378 women. 25.8% (3,973) ever smoked cannabis. Most use occurred in early adulthood. OR for ever-smokers: 1.27-1.30 across follow-ups. Regular smokers: OR 1.61. Occasional smokers: OR 1.19. Assessed at 2nd (2011-14), 3rd (2014-16), and 4th (2017-19) follow-ups.

How They Did This

Prospective cohort analysis of 15,378 women aged 65+ from the NIH Sister Study. Cannabis smoking history reported at enrollment (2003-2009). Cognitive complaints assessed via AD8 screener at three follow-ups (2011-2019). Multivariable joint models with adjustment for confounders.

Why This Research Matters

As the first generation of widespread cannabis users enters older age, understanding long-term cognitive effects becomes critical. This large prospective study suggests a dose-dependent association between cannabis history and later cognitive complaints.

The Bigger Picture

Baby boomers were the first generation with widespread cannabis use, and they're now reaching ages where cognitive decline becomes a concern. This study suggests that earlier cannabis use may contribute to cognitive vulnerability decades later, though the effect sizes are modest.

What This Study Doesn't Tell Us

Subjective cognitive complaints are not the same as dementia diagnosis. Cannabis use was recalled decades later (recall bias). Cannot separate cannabis effects from associated lifestyle factors. Mostly white sample. No information on cannabis use after enrollment.

Questions This Raises

  • ?Would objective cognitive testing confirm these subjective findings?
  • ?Is the risk specifically from smoking (combustion) or cannabis itself?
  • ?Do current older adults who use cannabis face different risks?

Trust & Context

Key Stat:
Evidence Grade:
Large prospective cohort with repeated measurements and appropriate covariate adjustment — methodologically strong for observational research.
Study Age:
Published in 2026, providing important long-term follow-up data as the first generation of widespread cannabis users ages.
Original Title:
History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.
Published In:
Neuroepidemiology, 1-11 (2026)
Database ID:
RTHC-08227

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

Can past cannabis use affect memory in old age?

This study of over 15,000 women found those who smoked cannabis earlier in life were 27-30% more likely to report memory and thinking complaints after age 65. Regular smokers had 61% higher odds, suggesting a dose-dependent relationship.

Should past cannabis users worry about dementia?

The study measured subjective complaints, not dementia diagnoses. The increased risk was modest (27-30%), and many other factors affect cognitive aging. However, regular past use showed stronger associations, suggesting it's worth monitoring cognitive health.

Read More on RethinkTHC

Cite This Study

RTHC-08227·https://rethinkthc.com/research/RTHC-08227

APA

Ding, Guoyong; Bohnert, Kipling M; Li, Chenxi; Plassman, Brenda L; Liang, Xiaoyu; Yuan, Yaqun; D'Aloisio, Aimee A; White, Alexandra J; Sandler, Dale P; Chen, Honglei. (2026). History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.. Neuroepidemiology, 1-11. https://doi.org/10.1159/000550276

MLA

Ding, Guoyong, et al. "History of Cannabis Smoking and Subjective Cognitive Complaints in Older Women.." Neuroepidemiology, 2026. https://doi.org/10.1159/000550276

RethinkTHC

RethinkTHC Research Database. "History of Cannabis Smoking and Subjective Cognitive Complai..." RTHC-08227. Retrieved from https://rethinkthc.com/research/ding-2026-history-of-cannabis-smoking

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.