From social and medical points of view, average life expectancy and healthy life expectancy (HLE) have been important markers worldwide [1]. More adequate effort will be required to maximize HLE for global situation of non-communicable diseases (NCDs). It includes decreasing risk prevention and increasing attention for upstream health determinants. These two factors are related to social expenditure as GDP ratio for each country, where recent data are shown from OECD (Figure 1) [2]. Higher ratios are observed in European countries, and Japan shows 23.8% of social expenditure, in which large budget are for the elderly people and health.

Figure 1: Social Expenditure as the Ratio of GDP from OECD.

The average life expectancy in 2019 is 81.41/87.45 years for male/female [3]. On the other hand, HLE was 72.68/75.38 years for M/F [4]. Then, there are approximately 8.73/12.06 year’s difference between both markers. Since 2001, the extended period of male healthy life expectancy became longer than that of women, and the gender gap has been slightly narrowed. There are some comments from Japan's Ministry of Health, Labor and Welfare (MHLW) [5]. They are i) it is important to extend HLE in line with Health Japan 21 (2^nd phase), ii) the national movement with this slogan is the "Smart Life Project" [6], iii) while extending HLE, it is crucial to set the goal for narrowing the gap with average life expectancy. In order to realize a vibrant society where each and every citizen can live a healthy and fulfilling life, and also to make the social security system sustainable, it would be necessary to extend HLE beyond the average lifespan.

MHLW is implementing various initiatives to achieve healthy longevity. HealthyJapan 21 (2^nd phase) began in 2013, and the goal of extending HLE has been achieved [7]. However, the final report in 2022 found that regional disparities in HLE had not been reduced for women. Therefore, the strategy continues to set goals and keep activities under "HealthyJapan 21 (3^rd phase)" from 2024 [8].

Japan Diabetes Society (JDS) has continued to check the average age at death for diabetic cases every 10 years for long [9]. Recent data were summarized during 2011-2020 for 68,555 diabetic cases and 164,621 non-diabetic cases. They were registered and analyzed form 208 multi-centers nationwide using questionnaire survey. The causes of death for 10-year period were calculated. The death cause was as follows: malignant neoplasm 38.9%, infection 17.0%, vascular disorder 10.9%, cerebrovascular disease (CVD) 5.2%, ischemic heart disease (IHD) 3.5%, and chronic renal failure (CRF) 2.3%. There were trends of increasing of malignancy and decreasing of vascular disorders.

These data exist from 1971-1980, 1981-1990, and until 2011-2022 for M/F (Figure 2). Latest report was presented in February, 2024 [10]. During 1971-1980, the average age at death of diabetic patients was 63.1/64.9 years for M/F, and difference between general population and diabetic patient was -10.3/-13.9 years, respectively. During 2011-2020, the data were 74.4/77.3 years and -7.2/-10.4 years. Thus, life expectancy for diabetes has been gradually increasing for long, which is greater than elevated life expectancy. Consequently, the difference of life expectancy became less between diabetes and general population. When comparing the average age at death in poor vs good control group (>8.4? vs <8.4%), the former showed 1.6 years lower. In particularly, lower result was found in poor control group, for IHD, CVD, heart failure, infection and diabetic coma.

Figure 2: Average Life Expectancy for 10 Years in General Population and Diabetic Patients in Japan: Male (Left), Female (Right).

As Figure 2 presented the average data of 10 years, Figure 3 shows the annual data for every 3 years. The latest results showed similar trends, in which the difference period was -8.73/-11.07 years for M/F, respectively.

Figure 3: Difference of Life Expectancy in Every 3 Years for General Population and Diabetic Patients: Male Data (Left), Female (Right).

Another report is found including large data for national wide [11]. The study used the largest health insurance database in Japan. From the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) data, population-based retrospective cohort study was conducted. Total cases over 6 years included 142 million patients (68/74 million cases in M/F), and diabetes cases were 6.5/4.6 million. The average age of death in diabetic cases showed 2.6 years lower than non-diabetes.

In summary, latest information about average life expectancy and healthy life expectancy (HLE) of diabetic cases in Japan was described. It is shorter than that of cases without diabetes. This report becomes hopefully useful reference for medical and statistic investigation in the future.

Conflict Of Interest

The authors declare no conflict of interest.

Funding

There was no funding received for this paper.

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