Table 4.

Relationships Between Muscle Cramp Frequency, Duration Length, Pain Severity, Location of Muscle Cramps, Time of Day, and Diabetic Retinopathy

	No DR (%)	NPDR (%)	PDR (%)
Frequency
Muscle cramp at least once a week	29% (7/24)	42% (10/24)	29% (7/24)
Muscle cramp at least once a month	39% (12/31)	45% (11/31)	26% (8/31)
Muscle cramp once within the last 3 months	53% (9/17)	41% (7/17)	6% (1/17)
No muscle cramp	62% (48/78)	34% (27/78)	4% (3/78)
p value	0.019	0.903	0.001
p for trend	0.002	0.505	0.001
Severity
VAS>3	26% (7/27)	48% (13/27)	26% (7/27)
VAS≤3	47% (21/45)	35% (16/45)	18% (8/45)
No muscle cramp	61% (48/78)	35% (27/78)	4% (3/78)
p value	0.005	0.437	0.004
p for trend	0.001	0.267	0.001
Duration
Lasting more than 10 minutes	0% (0/2)	100% (2/2)	0% (0/2)
Lasting 1–10 minutes	35% (19/54)	41% (22/54)	24% (13/54)
Lasting for less than 1 minute	56% (9/16)	31% (5/16)	13% (2/16)
No muscle cramp	61% (48/78)	35% (27/78)	4% (3/78)
p value	0.011	0.248	0.005
p for trend	0.001	0.256	0.001
Time of day
Both day and night	75% (6/8)	12.5% (1/8)	12.5% (1/8)
Night	39% (19/49)	47% (23/49)	14% (7/49)
Day	20% (3/15)	33% (5/15)	47% (7/15)
No muscle cramp	61% (48/78)	35% (27/78)	4% (3/78)
p value	0.03	0.222	0.001
p for trend	0.099	0.712	0.058