Table 5.

Adverse events reported during the one-year intervention by study arm

Vitamin D3
Adverse eventsPlacebo (n = 96)1,000 IU/day (n = 96)Pa2,000 IU/day (n = 99)Pa3,000 IU/day (n = 100)Pa
Symptomsb (%)
 Nausea38.544.81.0037.41.0031.01.00
 Fatigue75.079.21.0074.81.0079.01.00
 Headache62.565.61.0065.71.0069.01.00
 Weakness15.613.51.0010.11.0022.01.00
 Vomiting13.510.41.0016.21.0013.01.00
 Hypertension1.05.21.004.01.007.00.95
 Decreasing appetite33.321.90.9520.20.9522.00.95
 Confusion2.13.11.004.01.005.01.00
 Arrhythmia10.416.71.0014.11.0014.01.00
 Kidney disease0.00.01.000.01.000.01.00
Abnormal serum calciumc0.00.01.000.01.000.01.00
Abnormal serum creatininec0.02.11.000.01.000.01.00
  • aArms receiving vitamin D3 are compared with the placebo arm; adjusted P values for multiple comparisons using the Benjamini–Hochberg method.

  • bThe structured questionnaire administered at the five planned follow-up contacts included questions on each of these symptoms or problems, which represent main known or suspected symptoms of hypercalcemia. The table presents the frequency with which these symptoms or problems have been reported at least once during the one-year intervention.

  • cBased on blood specimen collected at the 12-month follow-up visit. Two participants had serum creatinine >85 μmol/L (86 and 94 μmol/L, respectively).