The Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT): Study design and participants.

BACKGROUND: Lifestyle and life-environment factors have undergone drastic changes in Japan over the last few decades. Further, many molecular epidemiologic studies have reported that genetic, epigenetic and other biomarker information may be useful in predicting individual disease risk.

METHODS: Japan Public Health Center-based Prospective Study for the Next Generation (JPHC-NEXT) was launched in 2011 to identify risk factors for lifestyle-related disease, elucidate factors which extend healthy life expectancy, and contribute toward personalized healthcare based on our more than 20 years' experience with the JPHC Study. Between 2011 and 2016, a baseline survey was conducted at 16 municipalities in 7 prefectures across the country. A self-administered questionnaire was distributed to all registered residents aged 40-74 which mainly asked about lifestyle factors, such as socio-demographic situation, personal medical history, smoking, alcohol and dietary habits. We obtained informed consent from each participant to participate in this long follow-up study of at least 20 years, including consent to the potential use of their residence registry, medical records, medical fee receipts, care insurance etc., and to the provision of biospecimens (blood and urine), including genomic analysis.

RESULTS AND CONCLUSION: As of December 31, 2016, we have established a population-based cohort of 115,385 persons (Response rate 44.1%), among whom 55,278 (47.9% of participants) have provided blood and urine samples. The participation rate was slightly higher among females and in the older age group. In conclusion, we have established a large-scale population-based cohort for next-generation epidemiological study in Japan.