INTRODUCTION: Previously, little attention has been paid as to how disturbances in the parathyroid hormone (PTH)-calcium-vitamin D-axis, such as secondary hyperparathyroidism (SHPT), relate to mortality amongst hip fracture patients. This study aimed to (1) determine if SHPT is associated with mortality in this group of patients, (2) investigate the association between serum (s-) PTH, s-total calcium, s-25-hydroxyvitamin D (s-25(OH)D) and mortality and (3) determine the prevalence of SHPT amongst hip fracture patients and a control group. METHOD: The study included 562 hip fracture patients (HF) (age=70 years) admitted to a Danish university hospital. The hip fracture patients were prospectively enrolled in a dedicated hip fracture database. Each hip fracture patient was exactly matched according to age and sex with two controls randomly chosen from a control population of 21,778 subjects who had s-PTH, s-total calcium and s-25(OH)D measured at the Copenhagen General Practitioners Laboratory after referral from their general practitioner. The control group (Con) thus consisted of 1124 subjects. RESULTS: General 1-year mortality: Con-female 8.4%, Con-male 15.3%, HF-female 24.6%, HF-male 33.3%, p