The effect of expanded serum cobalamin level criteria on the frequency of “suspected low serum cobalamin” in the elderly population
| Country of study (year) . | No. of subjects . | Frequency (%) of “suspect” cobalamin in the elderly . | |
|---|---|---|---|
| Standard cutpoint (∼ 200 ng/L)* . | Revised cutpoint (∼ 350 ng/L)† . | ||
| United States (1994)10 | 548 | 5.3 | 40.5 |
| Netherlands (1998)59 | 105 | 24.8 | 60.1 |
| United States (1999)11 | 591 | 11.8 | 50.4 |
| England (2007)72 | 2,403 | 8.6 | 71.7 |
| Country of study (year) . | No. of subjects . | Frequency (%) of “suspect” cobalamin in the elderly . | |
|---|---|---|---|
| Standard cutpoint (∼ 200 ng/L)* . | Revised cutpoint (∼ 350 ng/L)† . | ||
| United States (1994)10 | 548 | 5.3 | 40.5 |
| Netherlands (1998)59 | 105 | 24.8 | 60.1 |
| United States (1999)11 | 591 | 11.8 | 50.4 |
| England (2007)72 | 2,403 | 8.6 | 71.7 |
Data are from community-based surveys of medically unselected elderly populations with evaluable data.
The standard cutpoints defining low serum cobalamin levels in the 4 studies were 200, 203, 190, and 203 ng/L, respectively.
The expanded serum cobalamin cutpoints that were either recommended by study authors or are applied here solely for comparison purposes were 350, 352, 350, and 405 ng/L, respectively.