An estimation of deviation towards the mean for serum lipid fractions in patients followed for a varied duration.

We evaluated the deviation towards the mean and attempted to quantify it among the different lipid fractions in patients. The study was done retrospectively on patients who were judged to be metabolically stable and had repeated total cholesterol (TC), high density lipoprotein cholesterol (HDL) and triglyceride (TG) measured in a single laboratory with known coefficient of variation for repeated measurements. The patients and their data were separated into 3 groups. Group A (56 patients) evaluated the difference between the first and its average obtained from an average of 4 samples per patient within a mean of 9 months. Group B, examined pairs of data taken an average of 12 months apart. Group C, evaluated 45 patients with at least 3 data points each a year apart. Linear correlations were applied for the repeats versus the first samples. Highly significant correlations were obtained for all the groups. The slopes were less than one (generally between 0.66 and 0.85) and intercepts had positive values. This was seen even for the HDL whose range of values span 25 to 85 mg per cent. These results strongly supported deviation towards the mean such that from our calculation and in this population, a person with an initial TC of 200 mg per cent would have from 37 to 61 per cent chance of obtaining a significantly higher value if the test was repeated. The magnitude of the change would average 30 mg per cent for cholesterol and as much as 30 per cent of the initial values for TG. In this evaluation, the time intervals between repeats did not appear to influence the result. Yearly follow-up also did not seem to exhibit the effect of aging. However, the latter 2 conclusions rested on a small number of observations. It is suggested that several repeated estimations of these lipid fractions be done before a decision is made towards intervening. In instances of epidemiological studies, it is imperative to obtain representative repeated measurements since this deviation towards the mean will alter the slope of the events versus the lipid-variables.

Observation on the short and long term response to anti-lipemic drugs in southern Thailand.

Patients with dyslipidemia were evaluated with regard to the 5 drugs regimen: simvastatin (average dose, 11.8 mg/day), gemfibrozil (dose 963 mg/day), bezafibrate (433 mg/day), fenofibrate (211 mg/day) and acipimox (667 mg/day). The responses to the drug were divided into different time periods and the magnitude of responses were presented either as average changes in per cent from baseline or as proportion of patients (also in %) whose levels changed by a predetermined percentage. These predetermined percentage took into account the variation observed among patients who had more than 3 measurements during baseline. These levels for significant changes were 16 per cent for total cholesterol (TC), 25-30 per cent for high- and low-density lipoprotein (HDL and LDL), and 44 per cent for triglyceride (TG). Our subjects responded to the drugs within the range reported by other investigators except for acipimox which produced no alteration. Sixty to 100 per cent of patients reduced their TC by 16 per cent with an average change in TC of around -16 per cent to -24 per cent. Simvastatin and fenofibrate appeared most effective in altering TC. The HDL increased 10 per cent to 29 per cent depending on the drug but in terms of proportion that responded by an increment greater than 25 per cent, this was seen in only 23 per cent to 45 per cent of the patients. Long term follow-up which was possible only on 42 patients showed 11 who lessened their response and 6 whose response became more marked.(ABSTRACT TRUNCATED AT 250 WORDS)

Intravenous followed by oral antimicrobial therapy for staphylococcal endocarditis.

Nine men with ten episodes of staphylococcal endocarditis with valvular vegetation (except one) were treated with intravenous cloxacillin for an average of 10 days and followed by oral cloxacillin or dicloxacillin, both with probenecid, for a total duration of 4 wks. Monitoring of serum bactericidal titers (SBT) showed similar values between the two routes of therapy. All patients were bacteriologically and clinically cured. However, there were 3 recurrences, 2 were drug abusers. One nonabuser had the same staphylococcal species 8 months later. All survived the second episode. This preliminary study supports the contention that intravenous followed by oral therapy for staphylococcal endocarditis may be a viable and a more economical form of therapy.

In-hospital and follow-up mortality of patients with acute myocardial infarction.

Patients with definite acute MI who were admitted to Songkla University Hospital between 1982 and 1990 were studied. The 195 patients and 202 admissions were nearly equally distributed between these 65 and older versus those younger than 65. Three quarters were males. The in-hospital mortality was 19.5 per cent and 76.3 per cent of the deaths were from heart failure. Neither age nor gender determined the mortality once corrected for the Killip's staging. There was no difference in mortality when comparing Q versus non-Q MI, anterior versus inferior wall MI or males versus females. One hundred and thirty-eight patients could be followed for and average of 27.1 months. First year mortality was 11 per cent and the first 2 years was 14 per cent. The in-hospital mortality, representing the prethrombolytic era, appeared to be similar to values reported from the Thai and Western literature. The predominance of death from heart failure rather than from arrhythmia may be a consequence of delayed admission whence arrhythmic death had already occurred or patients will seek hospital advice only if highly symptomatic.

Streptococcal endocarditis treated with two-week antibiotic regimen: preliminary report of a partial oral regimen.

We reported 18 consecutive patients with penicillin-sensitive streptococcal IE (infective endocarditis). Twelve were successfully treated with a 2-wk course of penicillin G sodium (PGS) and gentamicin, the dosages of which were guided by minimal inhibitory concentration, minimal bactericidal concentration and serum bactericidal titer (SBT), followed by another six who were treated equally successfully with a one week PGS followed by a second week of amoxycillin together with the usual 2 wks of gentamicin. It is believed that oral therapy, after the initial 2-3 days of parenteral antimicrobial, may be adequate for penicillin-sensitive streptococcal IE.

Precipitous hypotension after nifedipine in pheochromocytoma: report of 2 cases.

Two patients with pheochromocytoma initially responded to oral or sublingual nifedipine with marked reduction in systolic blood pressure (range 50-160 mmHg) without concomitant increment in the heart rate or clinical consequences. This could possibly be due to the combination of hypovolemia and negative inotropism.

Double-blind evaluation of enalapril in patients with systolic heart failure.

Fifty-six patients with a mean age of 58 years, 14 females and 42 males, all with dominant systolic heart failure (33 in functional class 3 and 4) were randomised to receive either added placebo or added enalapril to their heart failure medication. There were 13 patients in this group who had their trial drug switched after a certain period to allow direct but blind comparison between placebo and enalapril. Cardiac mortality with enalapril was 32 per cent compared to 48 per cent with placebo at intervals after initiating therapy of 20.0 +/- 19.4 versus 14.3 +/- 11.5 months respectively. When compared to a preceding control period, 80 per cent of the enalapril patients improved in contrast to 21 per cent of the placebo. However, when a comparison was made directly between enalapril and placebo, enalapril was better in 31 per cent and placebo was better in 8 per cent of the patients. It is concluded that in certain patients with systolic heart failure from non-valvular and non-hypertensive causes, enalapril is beneficial when added to the conventional treatment. An argument is also presented that to cost-effectively identify the group who will benefit, a short term ACE-I trial after the conventional antifailure therapy can be considered in all patients with systolic heart failure.

Embolism and atrial fibrillation. A longitudinal follow-up.

Six hundred and forty-nine patients with proven chronic atrial fibrillation were followed for a total of 1,436 patient-years without anticoagulation. The patient were divided into 7 disease groups with each having an average age ranging from 39 to 69 years. Eleven per cent of the patients had systemic embolism prior to being registered for the follow-up. The diseases which had the highest incidence of embolism prior to being followed were the same as those producing the highest rate of systemic embolism while under observation. The disease groups were rheumatic valvular (predominantly mitral stenosis) and ischemic heart diseases. Their embolic rate were 3.9 to 5.1 emboli per 100 pt-yr. Other disease groups with lower embolic rates of 0 to 0.9 per 100 pt-yr were heart failure, non-rheumatic mitral regurgitation, atrial septal defect and thyrotoxicosis. Since the incidence of systemic embolism varied according to the primary disease, and since the hemorrhagic complication of anticoagulant therapy is finite, it is advised that low risk group may not benefit greatly from anticoagulation. However, the true low risk group has still to be properly determined.

Patients with prosthetic cardiac valves followed in southern Thailand.

Prospective follow-up of 174 post-prosthetic cardiac valves have been done at Prince of Songkla University and Hat Yai Regional hospitals since 1985. The total follow-up time was 549 patient-years (pt-yr). Thirty per cent had been followed for 1 year or less. Eighty-two per cent of the patients had their mitral valves replaced either singly or as part of a multiple replacement. Thirty per cent of the time, the prothrombin time was below therapeutic range. Major events did not appear to be different from other reports: 2.7 embolic events per 100 pt-yr, 3.2 major bleeds and 3.2 deaths which may eventually be as high as 4.4 if a portion of the lost patients was assumed to have died. Events related to prosthetic valves and anticoagulation seemed to occur predominantly 1-2 years after surgery.

Trimetazidine and stable angina a double-blind trial.

The effect of trimetazidine was evaluated in patients with stable angina by adding it to the other antianginal regimen in a double blind crossover design each of 8 week's duration. The method of evaluation made use of symptom recall, daily dairy of the intake of sublingual nitrates or of anginal discomfort and in some, symptom limited treadmill exercise stress test (EST). Thirty-six patients completed the trial. Symptom-wise, 16 patients could not differentiate the effect of the true tablet from the placebo. Eight had less and 12 had more angina while on the drug. Of the 17 evaluable EST, 9 showed no change in the degree of ischemic changes while 4 performed with less and 4 with more ischemia while on the drug. Symptom-wise and taking into account the pre and post trial periods, a placebo effect was not found to be dominant. It is concluded that trimetazidine does not improve angina among those already being treated with conventional doses of nitrates, beta and calcium blockers.

Is routine pre-operative electrocardiogram necessary?

Among 3,371 ECG (electrocardiograms) performed at Hat Yai Municipal hospital in 1981, at least 424 were done presumably for a routine preoperative investigation. Analysing the data file of each patient, it was found that 14 per cent had definitely abnormal ECGs of the type that generally implies ischemic heart disease. Another 9 per cent had ECGs that were possibly abnormal and needed, at least, a medical evaluation. However, only a fifth (22 out of 100) of those with abnormal ECGs were eventually examined and of these, less than half (9 out of 22) had their management altered. These results suggest that routine preoperative ECG lacks the potential usefulness given constraints present in several health centers in this country.