Multivariable-adjusted hazard ratios (95% CI) of all-cause mortality associated with a 50-U/L higher time-averaged serum ALP level in select subgroups. Multivariable models were adjusted for age, race, comorbidities, blood pressure, BMI, smoking status, medication use, enrolment period, estimated GFR, serum albumin, bicarbonate, AST, ALT, calcium, phosphorus, blood haemoglobin, WBC, percentage of lymphocytes in WBC and 24-h urine protein.