The surgical treatment for patients with primary hyperparathyroidism (HPT) remains controversial. Most physicians base the decision to operate on the 1990 National Institutes of Health (NIH) consensus guidelines. This report states that surgery is indicted only for patients who have a serum calcium level 1 mg per dL (0.25 mmol per L) above normal or have a history of life-threatening hypercalcemia, diminished renal function or loss of bone mass. However, more recent studies have found that even clinically “asymptomatic” patients with HPT feel dramatically better after surgery. To study this association in greater detail, Burney and colleagues evaluated patients with HPT who had high (greater than 10.9 mg per dL [2.72 mmol per L]) and low (less than 10.9 mg per dL) serum calcium levels. Their objective was to see if either group would have improved functional health status after surgery.
Patients selected were those with a diagnosis of primary HPT seen at a university endocrine surgery division. Before surgical intervention, patients were given a generic health status measure that covered demographic and condition-specific information. The eight domains of health status measured included: general health perception, physical function, physical and emotional limitations, social function, mental health, bodily pain and vitality. Additional medical information obtained from patients in the study included duration of HPT, weakness, bone pain, history of kidney stones and current medications. The serum calcium level used was the one obtained closest to the time of surgery. If patients were on a calcium-lowering agent, the pretreatment value was used.
A total of 155 patients were enrolled during a four-year period. Eighty-six patients had calcium levels less than 10.9 mg per dL and 69 had levels greater than or equal to 10.9 mg per dL. The mean ages for each group were 57 and 59 years, respectively. For both groups, approximately 75 percent were female and 25 percent male. Patients from the low and high baseline serum calcium groups had markedly lower health status scores than a normal reference population. However, there were no significant differences in the scores of the high and low calcium groups with values ranging from 41 to 75 in the various parameters assessed.
Two months after surgery, both groups of patients had improved in seven of the eight areas assessed by the survey. By five months, both groups continued to improve and achieved normal or near normal scores in six of eight domains tested. The patients in the high calcium group had less improvement in the degree of pain. Fatigue was reduced from 71 to 30 percent in the low calcium group and for the high calcium group the reduction was from 81 to 42 percent.
The authors believe the findings from this study support the use of surgery in patients with primary HPT. This is regardless of whether the serum calcium level is less than or greater than 10.9 mg per dL. They believe the absolute level of serum calcium is a poor indicator of functional status and not a good indicator of who would benefit from surgery. They further state that earlier surgery for patients diagnosed with primary HPT would appear to be as beneficial or perhaps more so than deferring surgery as is recommended by the current NIH guidelines.