Chronic loneliness and incident chronic lung diseases in two prospective cohorts.

BACKGROUND: Loneliness has been recognized as an independent predictor of incident chronic lung diseases. However, previous studies only focused on baseline loneliness status, not taking into consideration the changes in loneliness status during follow-up. This study examined the association of chronic loneliness and incident chronic lung diseases.

METHODS: This multicohort study used data from the US Health and Retirement Study (HRS) and the China Health and Retirement Longitudinal Study (CHARLS), consisting of participants aged 45 years or older from China and participants aged 50 years or older from the US. Participants' self-reported loneliness at baseline was treated as both a continuous variable and a dichotomous variable (low vs. High), and its change patterns were categorised as "stable low", "low-high", "high-low", and "stable high". Cox proportional hazards regression models were used to estimate the risk of developing chronic lung diseases.

FINDINGS: A total of 18,031 (HRS: 8636; CHARLS: 9395) individuals were included for loneliness change analyses. Compared with individuals assigned to "stable low" loneliness change status, significant increased risks of incident chronic lung diseases were observed among those belonging to "low-high", "high-low" and "stable high" groups in both cohorts ([CHARLS] "low-high", HR:1.46, 95 % CI:1.24-1.72; "high-low", HR:1.19, 95 % CI:1.02-1.38; "stable high", HR:1.60, 95 % CI:1.36-1.89; [HRS] "low-high", HR:1.39, 95 % CI:1.05-1.84; "high-low", HR:1.34, 95 % CI:1.03-1.75; "stable high", HR:1.60, 95 % CI:1.20-2.15).

CONCLUSIONS: Chronic loneliness was associated with higher risks of incident chronic lung diseases. Recovery or relief from loneliness might play an important role in the prevention of chronic lung diseases.