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Aims: To investigate the association between glycated haemoglobin (HbA1c) levels and chronic obstructive pulmonary disease (COPD) incidents in the general population, and the association between HbA1c levels and mortality in patients with COPD. Materials and Methods: We investigated the association of HbA1c levels with COPD risk in the general population in the UK Biobank, using data from 420 065 participants. Survival analysis was conducted for 18 854 patients with COPD. We used restricted cubic spline analysis to assess the dose‐response relationship between HbA1c levels and COPD risk and survival. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). Results: During a median follow‐up of 12.3 years, 11 556 COPD cases were recorded. HbA1c had a non‐linear relationship with COPD risk (p for non‐linearity <.05). Compared with the quintile 2 (32.2‐<34.3 mmol/mol), those with HbA1c levels above 38.7 mmol/mol (quintile 5) had a 22% (HR, 1.22, 95% CI: 1.15‐1.30) higher risk of COPD. Compared with the HbA1c decile 2 (30.5‐<32.2 mmol/mol), the HRs (95% CI) of COPD risk were 1.16 (1.03‐1.30) and 1.36 (1.24‐1.50) in the lowest HbA1c decile (<30.5 mmol/mol) and highest decile (≥41.0 mmol/mol), respectively. The increased COPD risk associated with HbA1c was more pronounced in younger, current smokers, passive smokers, and participants with a higher Townsend deprivation index (all p for interaction <.05). Among patients with COPD, 4569 COPD cases died (488 because of COPD) during a median follow‐up of 5.4 years. Regarding COPD survival, HbA1c had a non‐linear relationship with all‐cause death (p for non‐linearity <.05). Those with HbA1c quintile 5 (≥38.7 mmol/mol) had a 23% (HR, 1.23, 95% CI: 1.10‐1.37) higher risk of all‐cause death compared with the quintile 2 (32.2‐<34.3 mmol/mol). Compared with the HbA1c decile 4 (33.3‐<34.3 mmol/mol), those in the lowest HbA1c decile (<30.5 mmol/mol) and highest HbA1c decile (≥41.0 mmol/mol) had 22% (HR, 1.22; 95% CI: 1.01‐1.47) and 28% (HR, 1.28; 95% CI: 1.11‐1.48) higher risk for overall death. However, no significant association was observed between HbA1c levels and the risk of COPD‐specific death. Conclusions: Our findings indicated that lower and higher HbA1c levels were associated with a higher risk of COPD. In COPD cases, lower and higher HbA1c levels were associated with a higher COPD all‐cause death risk. [ABSTRACT FROM AUTHOR]

Aim: To investigate the associations of diabetes, prediabetes and diabetes duration with chronic obstructive pulmonary disease (COPD) risk and survival in the UK Biobank. Materials and Methods: We conducted a prospective analysis among 452 680 participants without COPD at baseline using UK Biobank data. Multivariable‐adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from Cox regression models. The dose–response relationship was explored using restricted cubic splines. A separate survival analysis was conducted for 12 595 patients with incident COPD. Results: Over a median follow‐up of 12.3 years, 12 595 cases of COPD were documented. Compared with the reference group, those with prediabetes and diabetes were associated with an 18% (HR 1.18 [95% CI: 1.13‐1.24]) and 35% (HR 1.35 [95% CI: 1.24‐1.47]) higher risk of COPD, respectively. Diabetes duration was associated with COPD risk, with multivariable HRs (95% CIs) of 1.23 (1.05‐1.44), 1.20 (1.04‐1.39) and 1.18 (1.01‐1.37) for diabetes duration of 7 years or longer, 3 to less than 7 years, and 1 to less than 3 years versus less than 1 year, respectively. Dose–response analysis revealed a non‐linear relationship between diabetes duration and COPD risk. Regarding COPD survival, COPD patients with prediabetes and diabetes had a 9% (HR 1.09 [95% CI: 1.00‐1.19]) and 21% (HR 1.21 [95% CI: 1.05‐1.41]) higher risk of overall death, respectively. Compared with the cases with a diabetes duration of less than 1 year, those with a diabetes duration of 7 years or longer were associated with a 46% higher risk of overall death (HR 1.46 [95% CI: 1.11‐1.92]). Conclusions: Our findings indicate that diabetes, prediabetes and a longer diabetes duration are associated with a higher risk of and worse survival for COPD. Future studies are warranted to determine the optimal way of diabetes control that might reduce COPD risk. [ABSTRACT FROM AUTHOR]