Table study population. The mean age of subjects

Table 1shows the mean values of age, TSH, T3, T4, ALT and AST of the study population. The mean age of subjects in the control group (N), Overtly hypothyroid (Oh) & Sub clinically hypothyroid (Sh), was 42.15 ± 1.86, 46±18 and 45.97±1.93 years respectively. Mean value of serum TSH was found highest in the Oh group (25.89±2.86µIU/ mL) & lowest in N group(2.38± 0.49µIU/ mL)  while T3 &T4 values were higher in N than the other groups (T3:1.68± .005ng/mL, T4: 8.50±1.59µg/ dL) and lowest in Oh group (T3: 0.94 ± 0.09ng/mL, T4: 4.30±0.28µg / dL).The mean value of serum ALT& AST level was highest in N group (ALT: 26.69±3.28 IU/L, AST: 33.70±5.12 IU/L) and lowest in the Sh group (ALT: 16.85±0.5 IU/L, AST: (17.86±0.98 IU/L).Results of multiple linear regression analysis16 using TSH, T3&T4 as independent variable while ALT&AST as dependent variable are given in table I, III and IV. Positive relation was found for both ALT and AST with TSH&T3 while a negative relation with T4 was found in N group. In Oh group positive relation for ALT with TSH and T3 and negative with T4 was observed.  Positive relation for ALT with TSH and T4 and negative with T3 in Sh was observed while AST had a negative relation with TSH, T3 &T4 in both patients group (Oh &Sh). The results of Pearson’s Correlation analysis17are given in table V -VII.Insignificant positive correlation for ALT with TSH in the entire study group was observed. In the N group, a very significant positive correlation was observed between AST and TSH (p =0.002).  Insignificant negative correlation for AST with TSH was found in both Oh and Sh groups respectively.Insignificant positive correlation for ALT with T3 in N, Oh and negative in Sh group was found. Similarly AST was found to have positive correlation withT3 in N and negative correlation in Oh and Sh group respectively. ALT showed insignificant correlation with T4 in N and Oh group and positive in Sh while negative correlation with T4 in all the study groups. Normal secretions of thyroid hormones are necessary for the normal functions of all vital organs of human body including liver. There is an intricate association between these two important organs of our body  and the data presented here,  reveals how a small alteration in the serum level of one marker of either thyroid or liver will affect the level of another marker in the study population. Our study  population  comprises of non-pregnant women(n=150)  in the age group of 18-75 years which were the  newly diagnosed cases of thyroid hypo functions hailing from different parts  of Khyber pakhtunkhwa in Pakistan . We observed significance differences in the ALT and AST level in all the three groups of our study population .The level of ALT and AST in both Oh and Sh was lower than N group of the study population.  Some earlier studies have reported that these enzymes may be elevated in hypothyroid patients but these studies have not mentioned, ethnicity, sex differences, geographical and genetically factors which may have influenced  the results of our study population18.                                                                                                                                                            Some studies have reported decreased activity of UDP-glucuronyl transferase in hypothyroid patients resulting in cholestatic jaundice and low excretion of bilirubin. Some reports show that liver abnormalities as observed in hypothyroid patients can be easily reversed with Thyroxin Replacement Therapy (TRT) in a few days with no significant liver damage 19. Significant correlation was observed between AST and TSH in the N group (p =0.002),while insignificant negative correlation of AST& TSH was found in the Oh and Sh groups respectively. AST was found to have insignificant negative correlation with T4 in all the three groups. No significant correlation was observed between ALT, TSH, T3 and T4 in any of the three groups. Other studies have also reported similar correlations between thyroid markers, Gamma Glutamyl Transferase and ALT20. Iodine deficiency is more prevalent in Khyber Pakhtunkhwa in northern Pakistan. According to the best of our knowledge no such paper has been found during our literature search from this area of Pakistan where the goiter prevalence is found to be 55% in plains to 80-90% in the northern mountainous region 10, 11. Conclusion:  Both liver enzymes (ALT) were found to be lower in the patients groups (Oh and Sh) as compared to control group (N). Our study reveals that there is a complex interdependency of thyroid gland and liver on each other, and a multisystem approach should be adopted while treating patients with diseases affecting either organ.Limitation of the study The study has got a number of limitations which could not be ignored. The study was conducted in only one tertiary care hospital and hence its results are not the true representations of the whole population. More over the study group comprised of only non-pregnant women excluding others and the sample size was too small consisting of only 150 NPW. The study group was mostly illiterate women folks, unable to communicate efficiently and hence making the collection of authentic data pertaining to their medical history and age, difficult. The time constraint was another limitation of the study. Lastly availability of finance was the major hurdle in widening the scope of the Study. Further studies involving lager populations will yield good results for better understanding the complex relationship between thyroid and liver axis in hypothyroid subjects.