保坂 唯仁

Background Research on the influence of heart failure on mortality after Alzheimer's disease diagnosis is limited. Objective To evaluate the association between comorbid heart failure and mortality following Alzheimer's disease diagnosis, particularly considering sex differences. Methods We analyzed administrative claims data from Japan, involving 32,363 individuals (11,064 men and 21,299 women) aged 75 or older newly diagnosed with Alzheimer's disease, with 7% having comorbid heart failure. Cox proportional hazard models and population attributable fractions (PAFs) were used to evaluate the association between comorbid heart failure and mortality within one year following Alzheimer's disease diagnosis. Results Individuals with Alzheimer's disease and heart failure had a multivariate-adjusted hazard ratio of 1.51 (95% confidence interval [CI], 1.32–1.73) for mortality during the one-year follow-up period compared to those with Alzheimer's disease and without heart failure. Subgroup analysis by sex revealed a higher mortality hazard ratio in women of 1.63 (95% CI, 1.36–1.95) than that in men of 1.39 (95% CI, 1.13–1.71). Further age and sex subgroup analysis indicated that women across all age brackets—75–79, 80–84, and ≥ 85 years—had higher mortality hazard ratios. The PAF for heart failure increased with age in both sexes, with women having higher PAFs than men, and the sex difference in PAF being most pronounced in the 75–79 age category (men: 1.4%, women: 4.0%). Conclusions Hazard ratios and PAFs for mortality associated with comorbid heart failure in newly diagnosed Alzheimer's disease are higher in women than in men, which persists across all age subgroups.

Objectives We evaluated the number of hospitalizations among public assistance recipients for each major classification according to the International Classification of Diseases 10th Revision (ICD-10), adjusting for sex and age differences in the general Japanese population. This study aimed to provide a comprehensive assessment of hospitalization patterns among public assistance recipients by disease category.Methods We used indirect methods to adjust for sex and age, with public assistance recipients and the entire Japanese population as the observation and reference groups, respectively. We calculated the standardized hospitalization ratios (SHRs) for each major classification based on the ICD-10. We only used publicly available government statistics, including data from the 2020 Patient Survey, for hospitalization rates according to sex, age, and major classification. Additionally, we used data from the 2020 National Survey on Public Assistance Recipients conducted for the number of public assistance recipients by sex and age groups and data from the 2020 Survey on the Actual Status of Medical Assistance conducted for the number of hospitalizations by major classification.Results After adjusting for age, the overall SHR was 1.49. The major classifications with the high SHRs for men and women were "V. Mental and behavioural disorders" (SHR for men; 4.06, women; 3.45) and "IV. Endocrine, nutritional, and metabolic diseases" (SHR for men; 2.40, women; 1.47). Conversely, the major classifications with low SHRs were "XVI. Certain conditions originating in the perinatal period" (SHR; 0.43) and "VII. Diseases of the eye and adnexa" (SHR; 0.44) for men. For women, these were "XV. Pregnancy, childbirth, and the puerperium" (SHR; 0.17) and "VII. Diseases of the eye and adnexa" (SHR; 0.27).Conclusion After adjusting for age, hospitalization status among public assistance recipients was higher overall than in the general Japanese population. However, if divided based on major classifications, higher and lower rates were observed compared with the general population. In assessing the status of medical assistance for public assistance recipients, research should be conducted by disease classification, considering the significant differences in age composition between public assistance recipients and the general Japanese population.