Results
A total of 336 hospitalized patients with suspicious or confirmed
COVID-19 were included in the study. Among them, HCQ was administered to
297 patients and 94 of them met the inclusion criteria. Twenty-eight
cases were excluded because of concomitant drug use that might affect
QTc and 66 cases were included in final analysis (Figure 1). The mean
age of the study population was 57.3 (sd=21.7) years and 54.6% was
older than 60 years old and 33% was female. Twenty patients (30.3%)
had diabetes mellitus (DM) and 25 (37.9%) patients had hypertension
(%37,9). In total, 67% of the cases were confirmed while 23% were
probable. The HCQ and AZT combination treatment were given 38% of the
study group. Twenty-four percent of the patients had ICU admission and
6.25% died. The ICU admission rate among patients who had HCQ
mono-theraphy and HCQ plus AZT were similar (25.0% and 23.1%,
respectively. p=0.86). The rate of mortality was also similar among mono
and combined theraphy group (5.1% and 8.0%, respectively. p=0.64)
The mean baseline QTc was 444.5 (sd=39.5) ms and was similar in both
males and females (442.7 and 448.1 respectively p=0.6). Forty-two
percent of the cases had baseline QTc more than 450 ms. Among patients
who has DM, the mean baseline QTc was 450.9 ms (sd=48.8) while it was
441.8 ms (sd=35) in non-diabetics (p=0.4). The mean interval of baseline
QTc was 455.6 (sd=35.8) ms in hypertensive patients, and 437.8 (sd=40.5)
ms in patients without hypertension (p=0.076)
In total, 63% of the patients’ QTc levels increased under HCQ treatment
and critical QTc prolongation occurred in 8 cases (12%) all of whom
were male (Table 1). In the critical QTc prolongation group the mean
level of baseline QTc was 457.4 (sd=55.4) ms, while it was 442.75
(sd=37.1) ms in cases without critical QTc prolongation (p=0.3). AZT was
given to 25 patients (38%). The
patients who had combination therapy with AZT had a mean baseline QTc
level of 448.5 (sd=45.7) ms, while the group without AZT had a mean
baseline interval of 442.1 (35.6) ms (p=0.53). The control QTc levels
were 460.3 (sd=48.6) ms in AZT combination group and were 451.2
(sd=51.8) ms in patients without AZT (p=0.48). Twenty-one cases used
oseltamivir in combination with HCQ (32%). Among these patients, the
mean baseline QTc level was 439.7 (sd=35.2) ms while it was 446.8
(sd=41.5) ms in non-oseltamivir group (p=0.5). The mean control QTc
levels were 465 (sd=52) ms and 449.8 (sd=49.5) ms in patients with and
without oseltamivir treatment, respectively (p=0.26).
The comparison of critically QT prolonged patients with others is shown
in Table 1. The mean age and frequency of hypertension were similar
among each group while male gender and DM were significantly higher
among patients with critical QTc prolongation. AZT use was higher in
critical QTc prolongation group but it was not significant (p=0.126)
while oseltamivir use was significantly higher in critical QTc
prolongation group (p=0.047). In the multivariate analysis, DM was found
to be higher among patient who had critical QTc prolongation (OR:5.8,
%95 Cl:1.11-30.32, p:0.037). Concomitant use of oseltamivir was also
higher in the same group (OR:5.3, %95 Cl:1,02-28, p:0.047. Table 2).
Although a significant proportion of critical QTc prolongation was
detected in our study population, none of our patients suffered from
cardiovascular end points.