Parental transmission of type 2 diabetes mellitus in a highly endogamous population

Table 1 Socio-demographic characteristics of patients with/without a family history of diabetes mellitus n (%)

	With family history of DM1(n = 1444)	Without family history of DM(n = 536)	P value
Age (yr)			< 0.001
18-30	346 (24.0)	72 (13.4)
30-39	280 (19.4)	66 (12.3)
40-49	258 (17.9)	132 (24.6)
50-59	400 (27.7)	194 (36.2)
≥ 60	160 (11.1)	72 (13.4)
Gender			0.041
Male	661 (45.8)	273 (50.9)
Female	783 (54.2)	263 (49.1)
Nationality			0.020
Qatari	838 (58.0)	342 (63.8)
Other Arabs	606 (42.0)	194 (36.2)
Educational level			0.154
Illiterate	240 (16.6)	71 (13.2)
Elementary	267 (18.5)	114 (21.3)
Intermediate	305 (21.1)	99 (18.5)
Secondary	381 (26.4)	152 (28.4)
University	251 (17.4)	100 (18.7)
Occupation			0.134
Housewife	370 (25.6)	128 (23.9)
Sedentary	356 (24.7)	162 (30.2)
Professional	249 (17.2)	97 (18.1)
Manual	153 (10.6)	53 (9.9)
Businessmen	127 (8.8)	39 (7.3)
Army/police clerk	189 (13.1)	57 (10.6)
Monthly household income (QR)			0.589
< 5000	93 (6.4)	39 (7.3)
5000-10 000	470 (32.5)	175 (32.6)
10 000-15 000	510 (35.3)	200 (37.3)
> 15 000	371 (25.8)	122 (22.8)
Consanguinity			0.001
Yes	556 (38.5)	162 (30.2)
No	888 (61.5)	374 (69.8)

¹Up to the third generation, two sided P values based on Pearson χ² test. DM: Diabetes mellitus; QR: Qatar Riyal.

Table 2 Familial history of diabetes mellitus among diabetic patients n (%)

	n = 1980
Family history of diabetes1
Negative	536 (27.1)
Positive	1444 (72.9)
Family relations
Father	437 (22.1)
Mother	503 (25.4)
Brother	281 (14.2)
Sister	184 (9.3)
Paternal uncle	244 (12.3)
Paternal aunt	195 (9.8)
Maternal uncle	325 (16.4)
Maternal aunt	293 (14.8)
Paternal grand father	235 (11.9)
Paternal grand mother	221 (11.2)
Maternal grand father	264 (13.3)
Maternal grand mother	272 (13.7)

¹Up to the third generation.

Table 3 Physical, metabolic characteristics and complications among diabetic patients according to family history of diabetes mellitus (n = 1980)

Parameters	Family history1		No family history of DM	P value
	Paternal history (n = 635)	Maternal history (n = 809)	(n = 536)
Age (yr)	44.9 ± 14	45.1 ± 15	46.7 ± 13.3	0.073
Duration of diagnosis (yr)	6.9 ± 4.2	7.3 ± 4.3	6.4 ± 3.3	0.001
BMI (kg/m2)	27.4 ± 4.9	26.8 ± 4.8	27.7 ± 4.9	0.033
Metabolic characteristics
Systolic blood pressure (mmHg)	129.9 ± 19.5	129.1 ± 18.1	127.1 ± 14.7	0.033
Diastolic blood pressure (mmHg)	81.3 ± 11	80.4 ± 10.5	79.4 ± 8.5	0.025
Fasting glucose (mmol/L)	9.9 ± 8.0	9.1 ± 5.0	9.1 ± 4.7	0.092
HbA1c	8.2 ± 2.2	7.9 ± 2.1	8.1 ± 2.2	0.188
Serum urea level	5.9 ± 1.5	6.3 ± 2.3	5.8 ± 1.7	0.135
Serum creatinine (mmol/L)	77.2 ± 9.5	78.1 ± 9.8	73.8 ± 8.6	0.371
Total cholesterol (mmol/L)	5.0 ± 1.1	4.8 ± 1.1	4.9 ± 1.2	0.095
Serum alkaline phosphate	94.6 ± 11.3	101.7 ± 13.8	100 ± 12.4	0.402
T2DM complications, n (%)
Sleep loss	88 (13.9)	99 (12.2)	36 (6.7)	< 0.001
Hypertension	167 (29.6)	156 (22.0)	111 (20.9)	0.001
Neuropathy	60 (9.4)	82 (10.1)	44 (8.2)	0.494
Retinopathy	112 (17.6)	108 (13.3)	61 (11.4)	0.006
Nephropathy	93 (14.6)	105 (13.0)	58 (10.8)	0.151
Antipathy	51 (8.0)	62 (7.7)	25 (4.7)	0.047

Data are expressed as absolute n (%) or mean ± SD.

¹Up to the third generation, two sided P values based on one way analysis of variance with post hoc Tukey’s test for quantitative variables and χ² test for categorical variables. DM: Diabetes mellitus; T2DM: Type 2 diabetes mellitus; BMI: Body mass index; HbA1c: Hemoglobin A1c.

Table 4 Physical and clinical characteristics of patients among consanguine and non consanguine parents (n = 1980)

Parameters	Consanguineous (n = 718)				Non-consanguineous (n = 1262)
	Paternal history of DM	Maternal history of DM	Without familial history	P value	Paternal history of DM	Maternal history of DM	Without familial history	P value
	(n = 233)	(n = 323)	(n = 162)		(n = 402)	(n = 486)	(n = 374)
Age (yr)	43.9 ± 14.7	45.1 ± 15.4	47.3 ± 13.4	0.058	45.5 ± 13.6	45.1 ± 14.8	46.3 ± 13.3	0.532
BMI (kg/m2)	27.4 ± 4.8	26.6 ± 4.9	28.1 ± 4.9	0.028	27.4 ± 5.0	26.9 ± 4.8	27.6 ± 4.8	0.428
Duration of DM (yr)	6.6 ± 3.9	7.2 ± 4.4	5.9 ± 2.9	0.004	7.2 ± 4.3	7.4 ± 4.2	6.7 ± 3.5	0.065
Metabolic characteristics
Systolic BP (mmHg)	129.6 ± 20.4	130.7 ± 17.9	125.9 ± 11.2	0.018	130.1 ± 19.1	128.2 ± 18.1	127.8 ± 16.5	0.224
Diastolic BP (mmHg)	81.3 ± 11.4	81.1 ± 10.7	78.2 ± 8.0	0.007	81.2 ± 11.4	79.9 ± 10.4	80.0 ± 9.1	0.220
Fasting glucose (mmol/L)	10.3 ± 8.9	8.9 ± 5.0	8.9 ± 5.4	0.071	9.7 ± 9.6	9.3 ± 5.0	9.3 ± 4.3	0.689
HbA1c (%)	7.8 ± 2.1	7.7 ± 2.1	7.8 ± 2.3	0.900	8.3 ± 2.4	7.9 ± 2.2	8.3 ± 2.1	0.121
Serum urea level	5.8 ± 3.0	6.2 ± 3.2	5.9 ± 4.4	0.622	5.9 ± 2.7	6.3 ± 3.1	5.7 ± 2.8	0.170
Creatinine (mmol/L)	71.9 ± 8.5	78.0 ± 9.8	72.4 ± 9.4	0.313	75.5 ± 9.9	76.2 ± 10.2	70.9 ± 8.6	0.372
Tot. cholesterol (mmol/L)	4.9 ± 1.1	4.8 ± 1.1	4.9 ± 1.2	0.626	5.0 ± 1.2	4.8 ± 1.1	4.9 ± 1.3	0.173
Serum alkaline phosphate	92.2 ± 11.1	99.3 ± 12.8	93.5 ± 12.2	0.683	95.9 ± 12.5	102.9 ± 13.2	104.6 ± 13.5	0.460
T2DM complications, n (%)
Sleep loss	44 (18.9)	40 (12.4)	12 (7.4)	0.003	44 (10.9)	59 (12.1)	24 (6.4)	0.017
Hypertension	67 (32.5)	59 (20.6)	31 (19.1)	0.002	100 (27.9)	97 (22.9)	80 (21.7)	0.114
Neuropathy	19 (8.2)	34 (10.5)	12 (7.4)	0.446	41 (10.2)	48 (9.9)	32 (8.6)	0.712
Retinopathy	44 (18.9)	41 (12.7)	13 (8.0)	0.007	68 (16.9)	67 (13.8)	48 (12.8)	0.231
Nephropathy	29 (12.4)	40 (12.4)	13 (8.0)	0.303	64 (15.9)	65 (13.4)	45 (12)	0.276
Antipathy	21 (9.0)	21 (6.5)	4 (2.5)	0.003	30 (7.5)	41 (8.4)	21 (5.6)	0.284
Hypoglycemia	62 (26.6)	91 (28.2)	46 (28.4)	0.899	111 (27.6)	113 (23.3)	99 (26.5)	0.299
Impotence	15 (6.4)	17 (5.3)	3 (1.9)	0.104	33 (8.2)	38 (7.8)	19 (5.1)	0.180

Data are expressed as absolute n (%) or mean ± SD. Two sided P values based on one way analysis of variance with post hoc Tukey’s test for quantitative variables and χ² test for categorical variables. DM: Diabetes mellitus; T2DM: Type 2 diabetes mellitus; BMI: Body mass index; HbA1c: Hemoglobin A1c; BP: Blood pressure.