Thyroid symptomatology across the spectrum of hypothyroidism and impact of levothyroxine supplementation in patients with severe primary hypothyroidism

Abstract

Objective: This study aimed to determine the clinical and biochemical profile of patients with severe primary hypothyroidism (SPH) (TSH ≥40 μIU/ml) as compared to milder forms of hypothyroidism and document improvement in hypothyroidism symptoms in SPH. Methods: Thyroid symptomatology and biochemistry were evaluated in SPH, non-severe overt primary hypothyroidism (NSOPH; TSH <40 μIU/ml), subclinical hypothyroidism (ScH) and healthy controls. A total of 598 consecutive patients of hypothyroidism were screened of which 461 patients' data were analyzed (91 SPH, 130 NSOPH and 240 ScH). Thyroid symptomatology was re-evaluated at 12 weeks follow-up in SPH following restoration of euthyroidism with levothyroxine. Results: The median (interquartile range) age of patients was 35 (28-42) years with 91.6% female. The commonly noted symptomatology were shortness of breath (93.4%) and fatigueability (91.2%) in SPH, fatigueability (68.46%) and limbs swelling (43.07%) in NSOPH, and fatigueability (56.67%) and shortness of breath (32.92%) in ScH. All symptomatology were significantly higher in SPH. Delayed tendon reflex, carpel tunnel syndrome and meno-metrorrhagia were exclusive in SPH. Occurrence of menstrual irregularities was 73.62%, 28.46% and 16.25% in SPH, NSOPH and ScH, respectively. SPH patients had significantly higher cholesterol and triglycerides. There was significant improvement in symptomatology, reduction in body weight (−2.11 kg), improvement in hemoglobin (+0.64 g/L) with fall in total cholesterol (−18.96%), LDL-cholesterol (−23.46%) and triglycerides (−13.53%) following euthyroidism restoration in subjects with SPH. Common residual symptoms were fatigue (10%), poor memory (8%) and menstrual irregularities (6%). Conclusion: Thyroid symptomatology differs significantly across spectrum of hypothyroidism, being significantly worse in SPH. Euthyroidism restoration is associated with reversal of majority of thyroid symptomatology.

Severity of Fatigue and Its Relationship with TSH before and after Levothyroxine Replacement Therapy in Patients with Primary Hypothyroidism

“…Fatigue severity evaluation: The fatigue severity scale (FSS) was used to evaluate fatigue both before and at 6 months after the beginning of levothyroxine replacement therapy. The FSS is one of the most commonly used fatigue questionnaires in chronic diseases [ 10 ] and is validated in our population [ 11 ]. The FSS consists of nine items that measure how fatigue affects motivation, exercise, physical functioning, carrying out duties, work, family, or social life.…”

“…The FSS consists of nine items that measure how fatigue affects motivation, exercise, physical functioning, carrying out duties, work, family, or social life. The scores are averaged across the nine statements and a score ≥36 indicates a clinically significant trait level of fatigue [ 10 , 11 ]. The delta of FSS (ΔFSS) was the difference between the FSS after treatment and the FSS before treatment.…”

Efficacy and Safety of Once Weekly Thyroxine as Compared to Daily Thyroxine in Managing Primary Hypothyroidism

“…[ 1 ] For best results, patients are advised to take thyroxine daily empty stomach, with at least 1 h gap between any food intake and thyroxine ingestion for optimal absorption, which many patients find difficult to follow over prolonged periods of time. [ 1 2 ] The need to keep thyroxine intake away from other medications, which the patient might be taking, further complicates the matter. [ 2 ] Commonly used medicines which impair thyroxine absorption from the gastrointestinal tract include antacids, calcium, and iron supplements.…”

“…[ 1 2 ] The need to keep thyroxine intake away from other medications, which the patient might be taking, further complicates the matter. [ 2 ] Commonly used medicines which impair thyroxine absorption from the gastrointestinal tract include antacids, calcium, and iron supplements. [ 2 ] Poor understanding of such issues often leads to over replacement of thyroxine by the treating doctor, resulting in fluctuations of TSH from low to normal to even high levels (brittle hypothyroidism).…”

“…[ 2 ] Commonly used medicines which impair thyroxine absorption from the gastrointestinal tract include antacids, calcium, and iron supplements. [ 2 ] Poor understanding of such issues often leads to over replacement of thyroxine by the treating doctor, resulting in fluctuations of TSH from low to normal to even high levels (brittle hypothyroidism). [ 3 ] Few studies have suggested that once weekly directly observed thyroxine therapy to improve compliance, translates into a better and more smooth control of hypothyroidism in patients having poorly compliant brittle hypothyroidism.…”