Table 1.
Details of cases and matched controls
| Variable | Female cases (n=501) | Male cases (n=173) | P value* | All cases (n=674) | All controls (n=2021) |
|---|---|---|---|---|---|
| Mean (SD) age at surgery (years) | 59.4 (14.3) | 54.8 (16.6) | 0.002 | 58.2 (15.0) | 58.2 (15.0) |
| Histology (No (%) of cases): | 0.87 | ||||
| Adenomas | 451 (90) | 155 (90) | 606 (90) | — | |
| Hyperplasia | 50 (10) | 18 (10) | 68 (10) | — | |
| Mean (SD) weight of removed glands (mg): | |||||
| Adenomas | 1799 (3139) | 3032 (8794) | 0.02 | 2105 (5175) | — |
| Hyperplasia | 3603 (7091) | 3565 (4294) | 0.13 | 3594 (6532) | — |
| Mean (SD) serum calcium (mmol/l)† | 1.57 (0.17) | 1.59 (0.15) | 0.37 | 1.58 (0.17) | — |
| No (%) with previous kidney stones‡ | 109 (22) | 58 (34) | 0.002 | 167 (25) | 15 (1) |
*
Comparison of male and female cases.
†
Ionised serum calcium concentration (upper normal range 1.35 mmol/l).
‡
At time of surgery (information was missing on one woman).