Of 199 subjects, 108 patients (54.3%) had dry eye syndrome. Prevalence of dry eye syndrome was significantly higher in longer duration of diabetes, but sex and age did not seem to affect dry eye syndrome.
Some studies evaluated dry eye syndrome in diabetic patients. In a cohort study on 3722 subjects were aged 48 to 91 years (65 ± 10 years) and 43% male. The overall prevalence of dry eye was 14.4%. Prevalence varied from 8.4% in subjects younger than 60 years to 19.0% in those older than 80 years. Age-adjusted prevalence in men was 11.4% compared with 16.7% in women . In another study a group of 140 patients aged 24–93, suffering from dry eye syndrome were assessed. A larger number of dry eye syndrome cases were identified in female patients, especially aged over 50 (80% of female and 20% of male). The most frequent general medical conditions diagnosed in the group of patients were as follows: arterial hypertension (men and women) and diabetes (women) . In one study during the 5-year interval between examinations, a history of dry eye developed in 322 of 2414 subjects, for an incidence of 13.3%. Incidence was significantly associated with age. After adjusting for age, incidence was greater in subjects with a history of allergy or diabetes, who used antihistamines or diuretics, and with poorer self-rated health . A cross- sectional study assessed one hundred patients with diabetes mellitus. Multiple regression analysis using the Schirmer test as a dependent variable and controlling for all the independent variables showed an association with autonomic neuropathy. No significant association was observed with the other variables, including the presence of auto antibodies. This study suggests that the low tear production seem in some DM patients is related to dysfunction of the autonomic nervous system . Seifart et al compared 92 patients with diabetes types I and II and aged from 7 to 69 years with a group of normal healthy controls comparable in number, age and sex. The results show that 52.8% of all diabetic subjects complained of dry eye symptoms, as against 9.3% of the controls. They concluded close monitoring of diabetic patients and good blood sugar regulation is important for the prevention of dry eye syndrome and retinopathy . In Jin study 100 patients with type II diabetes were compared with 80 normal healthy controls. In this study TBUT was significantly lower in type 2 diabetic patients . In Goebels study Schirmer test and tearing reflex was significantly lower in diabetic patients compared with control group . Jain reviewed the cases of 400 patients with dry eyes referred to a tertiary referral center. Of these, 80 (20%) had diabetes. Only two (2.5%) of these patients had Sjogren's syndrome, which could account for the dry ocular surface. In all the other patients, no other conditions were found to be a risk factor for dry eyes, and it was therefore presumed to be of diabetic origin . In other study the tests were carried out on a 100 individuals (50 healthy subjects in control group and 50 subjects suffering from diabetes) age 50–70 years. In that group of diabetic patients (N = 50) they found that 37 (74%) of them had lower values of tear secretion. 23 (46%) of them had lower values of TBUT. In the control group (N = 50) they found that 28 (56%) had lower values of tear secretion and 17 (34%) of them had lower values of TBUT . In our study frequency of dry eye syndrome was higher in diabetic patients with DR, but we did not find any study like that and larger studies need to evaluate relation between dry eye and DR.
Prevalence of dry eye in our study is very high. It might be due to aging, dry weather in this region and high prevalence of neurological disorder in type 2 diabetic patients.
Lack of control group and glycemic parameters assessment especially HbA1C could be mentioned as limitation of our study.
Of 199 diabetic patients, 140 patients (70.35%) had DR. The retinopathy was mild in 34 patients (17.1%), whereas 34(17.1%) patients had moderate NPDR, 22(11.1%) had sever NPDR and 50(25.1%) had PDR. These findings are higher than previous studies [18, 12, 22].
In our study prevalence of DR significantly increased with increasing of age, but it was not true in 65–82-year old subjects, and prevalence of DR in this group decreased. Some studies showed that the prevalence of DR in late-onset diabetic patients was lower than young-onset diabetic patients [19, 20]. A prevalence study was undertaken to estimate the prevalence of DR in patients diagnosed as having DM after the age of 70 years. Of 150 patients examined 21(14%) had some form of DR and 10 of these patients (6.6%) had threaten DR. Those patients with DR had a significantly higher median duration of diabetes (5.0 years) compared with those patients without DR (3.5 years) .
In our study there was significant association between sex and grades of DR. Lower grades of DR was more common in women and higher grades of DR was more common in men, such a relation was found in Rema et al 
Our results showed a significant association between prevalence of DR and diabetes duration, this pattern was seen in Klein et al. As the prevalence of DR varied from 28.8% in persons who had diabetes for less than five years to 77.8% in persons who had diabetes for 15 or more years .