Registration of visual impairment due to diabetic retinopathy in a subpopulation of Cambridgeshire

Figures & data

Table 1 Definitions of severe visual impairment and visual impairment used in the UK (apply to the better eye)

Severe visual impairment	Visual impairment
Worse than 3/60 (corrected visual acuity)	3/60 or 6/60 with full visual field
or	or
Worse than 6/60 with very contracted visual fields	6/24 or worse with moderate constriction of visual field
or	or
6/60 or above with a very contracted visual field especially in the lower part of the field	6/18 or better with gross visual field defects

Table 2 Causes of certification of visual impairment (VI) in Cambridgeshire (City, South, and Hunts), 2004–2005

Cause of visual Impairment (VI)	Number of occurrences	Percentage of patients n = 365	VI	Severe VI	0–15 years	15–64 years	65 + years
ARMD	224	61.4%	125	99	0	2	222
Glaucoma	43	11.8%	27	16	0	2	41
Retinitis pigmentosa	12	3.3%	5	7	0	7	5
Diabetic retinopathy	18	4.9%	13	5	0	3	15
Visual cortex disorder	19	5.2%	15	4	1	5	13
Optic neuropathy	27	7.4%	18	9	3	12	12
Retinal detachment	7	2%	5	2	0	2	5
Cause unstated	12	3.3%	6	6	4	1	7
Others	22	6.0%	14	8	1	7	14
Total occurrences	384		228	156	9	41	334
Total CVI forms	365		209	156	9	41	315

Table 3 Summary of registrations of visual impairment (VI) due to diabetic retinopathy (DR) in Cambridgeshire (City, South, and Hunts) (2004–2005)

Number of registrations with severe VI due to DR	5 (3.2% of severe VI registrations)
Number of registrations with partial VI due to DR	13 (6.2% of partial VI registrations)
Number of registrations with VI due to DR in working	0% of severe VI registrations
age group (16–64 years)	1.4% of partial VI registrations
Severe VI registration rate due to DR	6.5 per million population per year
Partial VI registration rate due to DR	17.1 per million population per year
Number of diabetics in Cambs City, South, Hunts 2005	10,842
Prevalence of diabetes	2.74%
Severe VI registration rate in diabetics	230 per million diabetics per year
Partial VI registration rate in diabetics	600 per million diabetics per year

Table 4 Demographics of Cambridgeshire (Census 2001)

	Cambridge City, South and Huntingdonshire	Cambridgeshire	England and Wales
Total population	395,933	552,658	52,041,916
Male	49.7%	49.5%	48.7%
Female	50.3%	50.5%	51.3%
Ethnic group
White	95.0%	95.9%	90.0%
Mixed	1.2%	1.0%	1.5%
Asian	1.7%	1.3%	4.5%
Black	0.7%	0.6%	3.0%
Chinese/Other	1.4%	1.2%	1.0%
Age (years)
0–15	19.3%	19.4%	18.7%
16–74	74.2%	73.6%	74.0%
75+	6.5%	7.0%	7.3%

Note: Percentages given are proportions of the total population of the column.