Exclude any pregnancy events that could be gestational diabetes.

This function takes the combined outputs from get_pregnancy_dates(), include_hba1c(), and exclude_potential_pcos() and uses diagnoses from LPR2 or LPR3 to exclude both elevated HbA1c tests and GLD purchases during pregnancy, as these may be due to gestational diabetes, rather than type 1 or type 2 diabetes. The aim is to identify pregnancies based on diagnosis codes specific to pregnancy-ending events (e.g. live births or miscarriages), and then use the dates of these events to remove inclusion events in the preceding months that may be related to gestational diabetes (e.g. elevated HbA1c tests or purchases of glucose-lowering drugs during pregnancy).

Usage

exclude_pregnancy(excluded_pcos, pregnancy_dates, included_hba1c)

Arguments

excluded_pcos

Output from exclude_potential_pcos().

pregnancy_dates

Output from get_pregnancy_dates().

included_hba1c

Output from include_hba1c().

Value

The same type as the input data, default as a tibble::tibble(). Has the same output data as the input exclude_potential_pcos(), except for a helper logical variable no_pregnancy that is used in later functions.

Details

After these exclusion functions have been applied, the output serves as inputs to two sets of functions:

1. The censored HbA1c and GLD data are passed to the "join_inclusions()" function for the final step of the inclusion process.

2. The censored GLD data is passed to the "get_only_insulin_purchases()", "get_insulin_purchases_within_180_days()", and "get_insulin_is_two_thirds_of_gld_doses()" helper functions for the classification of diabetes type.

See also

See the vignette("algorithm") for the logic used to filter these patients.

Examples

if (FALSE) { # \dontrun{
register_data <- simulate_registers(
  c(
    "lpr_adm",
    "lpr_diag",
    "kontakter",
    "diagnoser",
    "lmdb",
    "bef",
    "lab_forsker"
  ),
  n = 1000
)
lpr2 <- prepare_lpr2(register_data$lpr_adm, register_data$lpr_diag)
lpr3 <- prepare_lpr3(register_data$diagnoser, register_data$kontakter)

# Exclude pregnancy dates
register_data$lmdb |>
  include_gld_purchases() |>
  exclude_potential_pcos(register_data$bef) |>
  exclude_pregnancy(
    get_pregnancy_dates(lpr2, lpr3),
    include_hba1c(register_data$lab_forsker)
  )
} # }