Prevalence of mental health outcomes and effects of sex and mood or cognitive comorbidity in older adults during the COVID-19 pandemic

INTRODUCTION: Older adults are at greater risk for developing severe illness from SARS-COV2 infection and may be more vulnerable to negative mental health outcomes as a result of public health guidelines that increase social isolation. In the current study, we assessed mental health outcomes in a cohort of older adults with normal cognition (NC), past history of major depressive disorder (i.e., remitted; rMDD), or mild cognitive impairment (MCI) to determine the prevalence of clinically significant symptoms of depression, anxiety, general stress, and post-traumatic stress. Additionally, we assessed the effects of mood or cognitive diagnosis and sex on symptom severity. Based on the pre-pandemic literature, we predicted that the presence of rMDD or MCI diagnosis would be associated with increased severity of psychiatric symptoms during the COVID-19 pandemic. We also predicted that women would experience greater severity of psychiatric symptoms compared to men. METHODS: The study included 108 older adults (37 males, mean age=72.1 years) who were participating in existing longitudinal studies. The sample included 71 older adults with normal cognition (NC) based on normal neuropsychological test performance and who were free of lifetime history of psychiatric illness, 21 rMDD participants based on DSM5 criteria, and 16 MCI participants based on the presence of memory concerns, impaired performance on neuropsychological assessments, and intact functional independence. Participants completed self-report measures of depression, anxiety, and stress through video- or teleconferencing with a research assistant. Measures included the Patient Health Questionnaire-9 (PHQ-9) to assess depression, the Patient-Reported Outcomes Measurement Information System (PROMIS) to measure anxiety, the Perceived Stress Scale (PSS) to measure stress, and the Impact of Events Scale-Revised (IES-R) to assess post-traumatic stress symptoms. Prevalence rates of clinically significant psychiatric symptoms were expressed as the percentage of participants with total scores that exceed the normal cut-offs for each respective measure. Separate MANOVAs were used to examine the effects of diagnosis and sex. Non-normally distributed data (PHQ-9 and PROMIS total scores) were rank-transformed and entered into MANOVA. RESULTS: Within the sample of 108 participants, 33.7% exceeded the normal cut-off on the PHQ-9, 31.3% had clinically significant anxiety symptoms on the PROMIS-Anxiety, 35.5% had clinically significant stress scores on the PSS, and 38.3% had clinically significant post-traumatic stress scores on the IES-R. MANOVA showed statistically significant effects of diagnosis on all measures: PHQ-9 [F(2,90)=5.380, p=.006], PROMIS-Anxiety [F(2,90)=11.687, p<.001], PSS [F(2,90)=8.480, p<.001], and IES-R [F(2,90)=5.027, p=.009]. MDD participants scored higher on all measures compared to NC participants: PHQ-9 (p=.005), PROMIS-Anxiety (p<.001), PSS (p<.001), and IES-R (p=.004). In addition, MCI participants scored higher on the PSS compared to NC participants (p=.035). MANOVA showed significant effects of sex on all measures: PHQ-9 [F(1,91)=7.046, p=.009], PROMIS-Anxiety [F(1,91)=8.623, p=.004], PSS [F(1,91)=12.553, p<.001], and IES-R [F(1,91)=10.529, p=.002] such that women scored higher on all measures compared to men. CONCLUSIONS: Overall, over one-third of study participants reported clinically significant symptoms of depression, anxiety, general stress, and post-traumatic stress during the COVID-19 pandemic. These rates are higher than those described in population studies of older adults based on anonymous online surveys, which are reported to be 24.9% for depression, 19.4% for anxiety, 10.3% for stress, and 28.3% for post-traumatic stress; but are comparable to the prevalence rates of psychiatric symptoms in the general adult population. As predicted, presence of rMDD increased the severity of all psychiatric symptoms. However, MCI was also associated with increased stress compared to those with normal cognition, despite absence of current or past psychiatric illness. These findings suggest that older adults with previous depression or current MCI, as well as women overall, are particularly vulnerable to developing clinically significant psychiatric symptomatology during the COVID-19 pandemic. Limitations of the current study are the inclusion of participants in existing studies, as opposed to sampling from the general population and the relatively small sample size. Nevertheless, the current findings suggest that some clinical populations, including those with rMDD and MCI, as well as women overall, may benefit from receiving interventions for mental health during the current and future pandemics. THIS RESEARCH WAS FUNDED BY: This study was funded by the Ontario Ministry of Health and Long-Term Care Alternative Funding Plan. The funders had no role in the design of the study, analysis, or preparation of the manuscript.