A Mediation Analysis Examining High Risk, Anticholinergic Medication Use, Delirium, and Dementia After Major Surgery.

INTRODUCTION: Anticholinergic medications are known to cause adverse cognitive effects in community-dwelling older adults and medical inpatients, including dementia. The prevalence with which such medications are prescribed in older adults undergoing major surgery is not well described nor is their mediating relationship with delirium and dementia. We sought to determine the prevalence of high-risk medication use in major surgery patients and their relationship with the subsequent development of dementia. METHODS: This was a retrospective cohort study which used data between January 2013 and December 2019, in a large midwestern health system, including sixteen hospitals. All patients over age 50 undergoing surgery requiring an inpatient stay were included. The primary exposure was the number of doses of anticholinergic medications delivered during the hospital stay. The primary outcome was a new diagnosis of Alzheimer's disease and related dementias at 1-y postsurgery. Regression methods and a mediation analysis were used to explore relationships between anticholinergic medication usage, delirium, and dementia. RESULTS: There were 39,665 patients included, with a median age of 66. Most patients were exposed to anticholinergic medications (35,957/39,665; 91%), and 7588/39,665 (19.1%) patients received six or more doses during their hospital stay. Patients with at least six doses of these medications were more likely to be female, black, and with a lower American Society of Anesthesiologists class. Upon adjusted analysis, high doses of anticholinergic medications were associated with increased odds of dementia at 1 y relative to those with no exposure (odds ratio 2.7; 95% confidence interval 2.2-3.3). On mediation analysis, postoperative delirium mediated the effect of anticholinergic medications on dementia, explaining an estimated 57.6% of their association. CONCLUSIONS: High doses of anticholinergic medications are common in major surgery patients and, in part via a mediating relationship with postoperative delirium, are associated with the development of dementia 1 y following surgery. Strategies to decrease the use of these medications and encourage the use of alternatives may improve long-term cognitive recovery.

Major Surgery and Long Term Cognitive Outcomes: The Effect of Postoperative Delirium on Dementia in the Year Following Discharge.

BACKGROUND: Delirium is among the most common complications following major surgery. Delirium following medical illness is associated with the development of chronic cognitive decline. The objective of this study was to determine the association of postoperative delirium with dementia in the year following surgery. MATERIALS AND METHODS: This was a retrospective cohort study in a large health network (January 2013 to December 2019). All patients over age 50 undergoing surgery requiring an inpatient stay were included. Our main exposure was an episode of delirium. The primary outcome was a new dementia diagnosis in the 1 y following discharge. Secondary outcomes included hospital length of stay, non-home discharge destination, mortality and rehospitalizations in 1 y. RESULTS: There were 39,665 patients included, with a median age of 66. There were 4156 of 39,665 emergencies (10.5%). Specialties were general surgery (12,285/39,665, 31%) and orthopedics (11,503/39,665, 29%). There were 3327 (8.4%) patients with delirium. Delirious patients were older and were more likely to have comorbid conditions and undergone complex procedures. There were 1353 of 39,665 (3.5%) patients who developed dementia in the year following their surgery; 4930 of 39,665 (12.4%) who died; and 8200 of 39,665 (20.7%) who were readmitted. Delirium was associated with a new dementia diagnosis after adjusting for baseline characteristics (Odds ratio [OR] 13.9; 95% CI, 12.2-15.7). Similarly, delirium was also associated with 1 y mortality (OR 3.1; 95% CI 2.9-3.4) and readmission (OR 1.9, 95% CI 1.7-2.0). CONCLUSIONS: Postoperative delirium is the strongest factor associated with development of dementia in the year following a major operation. Strategies to prevent, identify, and treat delirium in the postoperative setting may improve long-term cognitive recovery.

Gender Differences in Insurance, Surgical Admissions and Outcomes at a Kenyan Referral Hospital.

INTRODUCTION: Gender is an important factor in determining access to healthcare resources. Women face additional barriers, especially in low- and middle-income countries. Surgical costs can be devastating, which can exacerbate engendered disparities. Kenya's National Hospital Insurance Fund (NHIF) aims to achieve universal coverage and protect beneficiaries from catastrophic health expenditures. We examine gender differences in NHIF coverage, health-seeking behavior, and surgical outcomes at a tertiary care hospital in Eldoret, Kenya. MATERIALS AND METHODS: All patients ≥13 years admitted to the general surgery service at Moi Teaching and Referral Hospital from January 2018-July 2018 were enrolled. Health records were retrospectively reviewed for demographic data, clinical parameters, NHIF enrollment, and cost information. Descriptive analyses utilized Wilcoxon Rank Sum, Pearson's Chi-square, and Fisher's Exact tests. RESULTS: 366 patients were included for analysis. 48.6% were enrolled in NHIF with significant female predominance (64.8% versus 37.9%, P < 0.0001). Despite differing coverage rates, male and female patients underwent surgery and suffered in-hospital mortality at similar rates. However, women only comprised 39.6% of admissions and were significantly more likely to delay care (median 60 versus 7 days, P < 0.0001), be diagnosed with cancer (26.6% versus 13.2%, P = 0.0024), and require a palliative procedure for cancer (44.1% versus 13.0%, P = 0.013). CONCLUSION: Many financial and cultural barriers exist in Kenya that prevent women from accessing healthcare as readily as men, persisting despite higher rates of NHIF coverage amongst female patients. Investigation into extra-hospital costs and social disempowerment for women may elucidate key needs for achieving health equity.