411

Clinica Chimica Acta, 78 (1977) 411-415 @ ElsevierlNorth-Holland Biomedical Press

CCA 8675

SERUM LIPIDS BEFORE AND AFTER PARATHYROIDECTOMY PATIENTS WITH PRIMARY HYPERPARATHYROIDISM

TONY

CHRISTENSSON

Department (Received

of Medicine, February

18th,

and KURT

EINARSSON

Serafimerlasarettet,

IN

*

S-l 12 83, Stockholm

(Sweden)

1977)

Summary Eight males and 36 females with hypercalcaemia were operated upon for primary hyperparathyroidism and parathyroid adenomata were revealed in every case. The serum levels of cholesterol and triglycerides were determined before the operations and 6, 12 and 18 months after them. Furthermore, the serum lipids of the patients were compared with those of a normocalcaemic sex- and age-matched control group. The serum cholesterol concentration in primary hyperparathyroidism was about 8-10% lower in both females and males compared with the corresponding control cases and the levels of serum triglycerides were about 22% and 60% lower. After operation the serum cholesterol concentration returned to a normal level and the triglycerides normalized. The results are discussed in the light of present knowledge about dietary calcium intake, primary hyperparathyroidism and lipid metabolism. Introduction During the last two decades several reports have appeared on the possible relation between water hardness and mortality from cardiovascular disease and between calcium intake and lipid metabolism. Epidemiological studies have demonstrated a negative correlation between water calcium ion concentration and cardiovascular disease mortality [l-4]. The effect of oral calcium on serum lipids has been investigated in short-term as well as long-term studies. Calcium ingestion seems to be associated with a decrease of the serum cholesterol level, whereas its effect on triglycerides is said to be more inconsistent [5-101. Recently De Moor et al. [ 111 reported that patients with primary hyperparathyroidism (PHPT) have an abnormally low serum cholesterol level which is normalized after parathyroidectomy. We have had the opportunity to do a retrospective study of the serum lipids in patients with PHPT. The present

412

paper reports on the serum levels of cholesterol and triglycerides before and after surgery for PHPT and compares these recordings in a normocalcaemic sex- and age-matched control group. Materials

in patients with those

and methods

The study covered 36 females and 8 males with hypercalcaemia who were operated upon because of suspected PHPT. The hypercalcaemia had been detected incidentally in health screening and all the subjects were found to have parathyroid adenomata, always single and usually dominated by chief cells. Only 30% of the patients had a history or current finding of renal calculi and 20% suffered from skeletal derangement with subperiosteal resorption, which indicates that in most cases the hyperparathyroidism was presumably of rather short duration and/or rather moderate in degree [12--141. The extirpation of parathyroid adenomata led in every case to a normalization of the serum calcium level. Clinical data on the patients are given in Table I. As part of the routine examination of the patients the serum concentrations of cholesterol and triglycerides were determined twice within 6 months prior to the operation and 3 times after the operation at intervals of 6 months. The serum recordings of the patients with PHPT were matched with those of normocalcaemic control cases before operation. Each control case had to be of the same sex and have been born during the same year and month as the corresponding observation subject (Table I). The system permitted a comparative study on matched, paired samples [ 151. Serum cholesterol levels were measured using a Technicon Auto Analyzer (Technicon Instruments Corp. Tarrytown, N.Y.) and triglycerides by a method by Laurel1 [ 161. The serum calcium levels were determined by Auto Analyzer or atomic absorption spectrophotometry (Perkin-Elmer, Norwalk, Conn., U.S.A.). Results The serum cholesterol level in the patients with PHPT, both females and males, was about 8-109~ lower than that of corresponding controls (Table II). After operation the cholesterol concentrations rose to normal levels, which remained constant in three determinations recorded at intervals of 6 months. The mean values of the triglyceride concentrations were about 22% and 60% lower in the females and males respectively with PHPT compared with corresponding control groups (Table II). After operation the triglyceride concentrations normalized. The postoperative increase of the serum lipids was not accompanied by, or could not be explained by changes in body weight or serum T, values (Table I). Discussion The present results show that patients with hypercalcaemic PHPT have lower serum lipids, cholesterol as well as triglycerides, than normocalcaemic controls. Furthermore, the serum lipids were normalized after operation for PHPT with

TABLE

I

DATA

Sex

F F

M M

F+M F+M

Subjects

PHPT

Controls

PHPT Controls

PHPT Controls

ON

as mean

44 44

8 8

36 36

N

PHPT

54.9 54.9

52.6 52.6

55.5 55.5

(Years)

Age

+ 0.7 r 0.7

i 2.5 + 2.5

+ 0.8 & 0.8

Relative

WITH

+ S.E.M.

GROUP

PATIENTS

CONTROL

P < 0.001.

are expressed

operation,

Data

SEX-MATCHED

CLINICAL

body

+ 2 i 2

104 103

* 3 f 2

104.5 3 105 f 4

103 102

Before

103

101 -

106

After

i 4

-t 2

r 2

(%)

2.78 2.57

2.75 2.54

2.79 2.58

Before

Serum

calcium

(cm))

? 0.02 + 0.02***

+ 0.02 + 0.02***

? 0.02 + 0.04***

length

PARATHYROID

(kg)/body

AFTER

weight

weight

[body

6 MONTHS

body

% =

AND

Relative

weight

BEFORE

-

2.56 -

2.55 -

2.56 -

After

(mmol/l)

1001

***

+ 0.02”**

? 0.03

ON

(mmol/l)

104 102

102 100

106 104

2 2 f 2

i 4 f 4

r 2 * 4

Befored

T4

102 -

100 -

104 -

After

different

from

i 2

* 2

+ 4

A NORMOCALCAEMIC

* * * Significantly

AND

+ 0.03***

X 100.

OPERATION

PHPT

AGE-

before

AND

414

TABLE

II

SERUM TION

LIPIDS AND

6,

IN 12

AND

SEX-MATCHED

Data

are

***p