[Relationship between the number of public health nurses and the total number of people receiving home-visit nursing services for mental health/intractable diseases, and those numbers' regional differences].

Objectives　The primary aim of this study was to clarify the relationship between the number of public health nurses (PHNs) and the total number of people who received home-visit nursing services for mental health or intractable diseases. The secondary aim was to clarify the extent of regional differences in the number of PNHs and mental health or intractable diseases.Methods　This study used the total number of people who received home-visit nursing services for mental health or intractable diseases in 2019 from the Portal Site of Official Statistics of Japan (e-Stat) and population and area data in January 2020. Single and multiple regression analyses (covariates: population and area) were performed on the relationship between the number of PHNs per 100,000 population (abbreviated as "ratios of PHNs") and the total number of people who received home-visit nursing services for mental health or intractable diseases per 100,000 population (abbreviated as "mental health/intractable disease achievements"). Regional differences in ratios of PHNs and mental health/intractable disease achievement were examined using mean, standard deviation, maximum/minimum values, and Gini coefficients. Analyses were performed for each of the five units: the prefectures as a whole, prefectural public health centers, municipalities within the jurisdiction of prefectural public health centers, and cities in which public health centers are established (including or not including special wards).Results　Regression analyses indicated a positive relationship between the ratios of PHNs and mental health/intractable disease achievements. Multiple regression analysis indicated that both achievements were positively associated with population size and negatively associated with area size. The largest regression coefficients between the ratios of PHNs and achievements were 34.07 and 5.48 regarding mental health achievements and intractable disease achievements, respectively. For regional differences, the smallest Gini coefficient was the ratios of PHNs, and the largest was intractable disease achievements. The smallest and largest coefficient of the prefectures as a whole was 0.15 and 0.34, respectively. The maximum/minimum values of the prefectures as a whole also indicated that the smallest was 3.8 in the ratio of PHNs and the largest was 30.0 in intractable disease achievement.Conclusions　Increasing number of PHNs is needed to provide more home-visit nursing services for mental health and intractable diseases. It is particularly important to fill up the larger number of PHNs in smaller populations or larger area prefectures. Due to regional differences in the home-visit nursing service, it is important to promote the increase in the level of these activities.